An I/O controller for virtual pinball machines: accelerometer nudge sensing, analog plunger input, button input encoding, LedWiz compatible output controls, and more.

Dependencies:   mbed FastIO FastPWM USBDevice

Fork of Pinscape_Controller by Mike R


This is Version 2 of the Pinscape Controller, an I/O controller for virtual pinball machines. (You can find the old version 1 software here.) Pinscape is software for the KL25Z that turns the board into a full-featured I/O controller for virtual pinball, with support for accelerometer-based nudging, a real plunger, button inputs, and feedback device control.

In case you haven't heard of the concept before, a "virtual pinball machine" is basically a video pinball simulator that's built into a real pinball machine body. A TV monitor goes in place of the pinball playfield, and a second TV goes in the backbox to serve as the "backglass" display. A third smaller monitor can serve as the "DMD" (the Dot Matrix Display used for scoring on newer machines), or you can even install a real pinball plasma DMD. A computer is hidden inside the cabinet, running pinball emulation software that displays a life-sized playfield on the main TV. The cabinet has all of the usual buttons, too, so it not only looks like the real thing, but plays like it too. That's a picture of my own machine to the right. On the outside, it's built exactly like a real arcade pinball machine, with the same overall dimensions and all of the standard pinball cabinet hardware.

A few small companies build and sell complete, finished virtual pinball machines, but I think it's more fun as a DIY project. If you have some basic wood-working skills and know your way around PCs, you can build one from scratch. The computer part is just an ordinary Windows PC, and all of the pinball emulation can be built out of free, open-source software. In that spirit, the Pinscape Controller is an open-source software/hardware project that offers a no-compromises, all-in-one control center for all of the unique input/output needs of a virtual pinball cabinet. If you've been thinking about building one of these, but you're not sure how to connect a plunger, flipper buttons, lights, nudge sensor, and whatever else you can think of, this project might be just what you're looking for.

You can find much more information about DIY Pin Cab building in general in the Virtual Cabinet Forum on Also visit my Pinscape Resources page for more about this project and other virtual pinball projects I'm working on.


  • Pinscape Release Builds: This page has download links for all of the Pinscape software. To get started, install and run the Pinscape Config Tool on your Windows computer. It will lead you through the steps for installing the Pinscape firmware on the KL25Z.
  • Config Tool Source Code. The complete C# source code for the config tool. You don't need this to run the tool, but it's available if you want to customize anything or see how it works inside.


The new Version 2 Build Guide is now complete! This new version aims to be a complete guide to building a virtual pinball machine, including not only the Pinscape elements but all of the basics, from sourcing parts to building all of the hardware.

You can also refer to the original Hardware Build Guide (PDF), but that's out of date now, since it refers to the old version 1 software, which was rather different (especially when it comes to configuration).

System Requirements

The new config tool requires a fairly up-to-date Microsoft .NET installation. If you use Windows Update to keep your system current, you should be fine. A modern version of Internet Explorer (IE) is required, even if you don't use it as your main browser, because the config tool uses some system components that Microsoft packages into the IE install set. I test with IE11, so that's known to work. IE8 doesn't work. IE9 and 10 are unknown at this point.

The Windows requirements are only for the config tool. The firmware doesn't care about anything on the Windows side, so if you can make do without the config tool, you can use almost any Windows setup.

Main Features

Plunger: The Pinscape Controller started out as a "mechanical plunger" controller: a device for attaching a real pinball plunger to the video game software so that you could launch the ball the natural way. This is still, of course, a central feature of the project. The software supports several types of sensors: a high-resolution optical sensor (which works by essentially taking pictures of the plunger as it moves); a slide potentionmeter (which determines the position via the changing electrical resistance in the pot); a quadrature sensor (which counts bars printed on a special guide rail that it moves along); and an IR distance sensor (which determines the position by sending pulses of light at the plunger and measuring the round-trip travel time). The Build Guide explains how to set up each type of sensor.

Nudging: The KL25Z (the little microcontroller that the software runs on) has a built-in accelerometer. The Pinscape software uses it to sense when you nudge the cabinet, and feeds the acceleration data to the pinball software on the PC. This turns physical nudges into virtual English on the ball. The accelerometer is quite sensitive and accurate, so we can measure the difference between little bumps and hard shoves, and everything in between. The result is natural and immersive.

Buttons: You can wire real pinball buttons to the KL25Z, and the software will translate the buttons into PC input. You have the option to map each button to a keyboard key or joystick button. You can wire up your flipper buttons, Magna Save buttons, Start button, coin slots, operator buttons, and whatever else you need.

Feedback devices: You can also attach "feedback devices" to the KL25Z. Feedback devices are things that create tactile, sound, and lighting effects in sync with the game action. The most popular PC pinball emulators know how to address a wide variety of these devices, and know how to match them to on-screen action in each virtual table. You just need an I/O controller that translates commands from the PC into electrical signals that turn the devices on and off. The Pinscape Controller can do that for you.

Expansion Boards

There are two main ways to run the Pinscape Controller: standalone, or using the "expansion boards".

In the basic standalone setup, you just need the KL25Z, plus whatever buttons, sensors, and feedback devices you want to attach to it. This mode lets you take advantage of everything the software can do, but for some features, you'll have to build some ad hoc external circuitry to interface external devices with the KL25Z. The Build Guide has detailed plans for exactly what you need to build.

The other option is the Pinscape Expansion Boards. The expansion boards are a companion project, which is also totally free and open-source, that provides Printed Circuit Board (PCB) layouts that are designed specifically to work with the Pinscape software. The PCB designs are in the widely used EAGLE format, which many PCB manufacturers can turn directly into physical boards for you. The expansion boards organize all of the external connections more neatly than on the standalone KL25Z, and they add all of the interface circuitry needed for all of the advanced software functions. The big thing they bring to the table is lots of high-power outputs. The boards provide a modular system that lets you add boards to add more outputs. If you opt for the basic core setup, you'll have enough outputs for all of the toys in a really well-equipped cabinet. If your ambitions go beyond merely well-equipped and run to the ridiculously extravagant, just add an extra board or two. The modular design also means that you can add to the system over time.

Expansion Board project page

Update notes

If you have a Pinscape V1 setup already installed, you should be able to switch to the new version pretty seamlessly. There are just a couple of things to be aware of.

First, the "configuration" procedure is completely different in the new version. Way better and way easier, but it's not what you're used to from V1. In V1, you had to edit the project source code and compile your own custom version of the program. No more! With V2, you simply install the standard, pre-compiled .bin file, and select options using the Pinscape Config Tool on Windows.

Second, if you're using the TSL1410R optical sensor for your plunger, there's a chance you'll need to boost your light source's brightness a little bit. The "shutter speed" is faster in this version, which means that it doesn't spend as much time collecting light per frame as before. The software actually does "auto exposure" adaptation on every frame, so the increased shutter speed really shouldn't bother it, but it does require a certain minimum level of contrast, which requires a certain minimal level of lighting. Check the plunger viewer in the setup tool if you have any problems; if the image looks totally dark, try increasing the light level to see if that helps.

New Features

V2 has numerous new features. Here are some of the highlights...

Dynamic configuration: as explained above, configuration is now handled through the Config Tool on Windows. It's no longer necessary to edit the source code or compile your own modified binary.

Improved plunger sensing: the software now reads the TSL1410R optical sensor about 15x faster than it did before. This allows reading the sensor at full resolution (400dpi), about 400 times per second. The faster frame rate makes a big difference in how accurately we can read the plunger position during the fast motion of a release, which allows for more precise position sensing and faster response. The differences aren't dramatic, since the sensing was already pretty good even with the slower V1 scan rate, but you might notice a little better precision in tricky skill shots.

Keyboard keys: button inputs can now be mapped to keyboard keys. The joystick button option is still available as well, of course. Keyboard keys have the advantage of being closer to universal for PC pinball software: some pinball software can be set up to take joystick input, but nearly all PC pinball emulators can take keyboard input, and nearly all of them use the same key mappings.

Local shift button: one physical button can be designed as the local shift button. This works like a Shift button on a keyboard, but with cabinet buttons. It allows each physical button on the cabinet to have two PC keys assigned, one normal and one shifted. Hold down the local shift button, then press another key, and the other key's shifted key mapping is sent to the PC. The shift button can have a regular key mapping of its own as well, so it can do double duty. The shift feature lets you access more functions without cluttering your cabinet with extra buttons. It's especially nice for less frequently used functions like adjusting the volume or activating night mode.

Night mode: the output controller has a new "night mode" option, which lets you turn off all of your noisy devices with a single button, switch, or PC command. You can designate individual ports as noisy or not. Night mode only disables the noisemakers, so you still get the benefit of your flashers, button lights, and other quiet devices. This lets you play late into the night without disturbing your housemates or neighbors.

Gamma correction: you can designate individual output ports for gamma correction. This adjusts the intensity level of an output to make it match the way the human eye perceives brightness, so that fades and color mixes look more natural in lighting devices. You can apply this to individual ports, so that it only affects ports that actually have lights of some kind attached.

IR Remote Control: the controller software can transmit and/or receive IR remote control commands if you attach appropriate parts (an IR LED to send, an IR sensor chip to receive). This can be used to turn on your TV(s) when the system powers on, if they don't turn on automatically, and for any other functions you can think of requiring IR send/receive capabilities. You can assign IR commands to cabinet buttons, so that pressing a button on your cabinet sends a remote control command from the attached IR LED, and you can have the controller generate virtual key presses on your PC in response to received IR commands. If you have the IR sensor attached, the system can use it to learn commands from your existing remotes.

Yet more USB fixes: I've been gradually finding and fixing USB bugs in the mbed library for months now. This version has all of the fixes of the last couple of releases, of course, plus some new ones. It also has a new "last resort" feature, since there always seems to be "just one more" USB bug. The last resort is that you can tell the device to automatically reboot itself if it loses the USB connection and can't restore it within a given time limit.

More Downloads

  • Custom VP builds: I created modified versions of Visual Pinball 9.9 and Physmod5 that you might want to use in combination with this controller. The modified versions have special handling for plunger calibration specific to the Pinscape Controller, as well as some enhancements to the nudge physics. If you're not using the plunger, you might still want it for the nudge improvements. The modified version also works with any other input controller, so you can get the enhanced nudging effects even if you're using a different plunger/nudge kit. The big change in the modified versions is a "filter" for accelerometer input that's designed to make the response to cabinet nudges more realistic. It also makes the response more subdued than in the standard VP, so it's not to everyone's taste. The downloads include both the updated executables and the source code changes, in case you want to merge the changes into your own custom version(s).

    Note! These features are now standard in the official VP releases, so you don't need my custom builds if you're using 9.9.1 or later and/or VP 10. I don't think there's any reason to use my versions instead of the latest official ones, and in fact I'd encourage you to use the official releases since they're more up to date, but I'm leaving my builds available just in case. In the official versions, look for the checkbox "Enable Nudge Filter" in the Keys preferences dialog. My custom versions don't include that checkbox; they just enable the filter unconditionally.
  • Output circuit shopping list: This is a saved shopping cart at with the parts needed to build one copy of the high-power output circuit for the LedWiz emulator feature, for use with the standalone KL25Z (that is, without the expansion boards). The quantities in the cart are for one output channel, so if you want N outputs, simply multiply the quantities by the N, with one exception: you only need one ULN2803 transistor array chip for each eight output circuits. If you're using the expansion boards, you won't need any of this, since the boards provide their own high-power outputs.
  • Cary Owens' optical sensor housing: A 3D-printable design for a housing/mounting bracket for the optical plunger sensor, designed by Cary Owens. This makes it easy to mount the sensor.
  • Lemming77's potentiometer mounting bracket and shooter rod connecter: Sketchup designs for 3D-printable parts for mounting a slide potentiometer as the plunger sensor. These were designed for a particular slide potentiometer that used to be available from an seller but is no longer listed. You can probably use this design as a starting point for other similar devices; just check the dimensions before committing the design to plastic.

Copyright and License

The Pinscape firmware is copyright 2014, 2021 by Michael J Roberts. It's released under an MIT open-source license. See License.

Warning to VirtuaPin Kit Owners

This software isn't designed as a replacement for the VirtuaPin plunger kit's firmware. If you bought the VirtuaPin kit, I recommend that you don't install this software. The VirtuaPin kit uses the same KL25Z microcontroller that Pinscape uses, but the rest of its hardware is different and incompatible. In particular, the Pinscape firmware doesn't include support for the IR proximity sensor used in the VirtuaPin plunger kit, so you won't be able to use your plunger device with the Pinscape firmware. In addition, the VirtuaPin setup uses a different set of GPIO pins for the button inputs from the Pinscape defaults, so if you do install the Pinscape firmware, you'll have to go into the Config Tool and reassign all of the buttons to match the VirtuaPin wiring.

Sat Apr 30 17:43:38 2016 +0000
TLC5940 with SPI DMA setup in interrupt handler (not quite working)

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mjr 26:cb71c4af2912 1 // Pinscape Controller TLC5940 interface
mjr 26:cb71c4af2912 2 //
mjr 26:cb71c4af2912 3 // Based on Spencer Davis's mbed TLC5940 library. Adapted for the
mjr 54:fd77a6b2f76c 4 // KL25Z and modified to use SPI with DMA to transmit data. The DMA
mjr 54:fd77a6b2f76c 5 // scheme results in greatly reduced CPU load. This version is also
mjr 54:fd77a6b2f76c 6 // simplified to remove dot correction and status input support, which
mjr 54:fd77a6b2f76c 7 // the Pinscape Controller app doesn't use.
mjr 26:cb71c4af2912 8
mjr 26:cb71c4af2912 9
mjr 26:cb71c4af2912 10 #ifndef TLC5940_H
mjr 26:cb71c4af2912 11 #define TLC5940_H
mjr 26:cb71c4af2912 12
mjr 54:fd77a6b2f76c 13 #include "FastPWM.h"
mjr 54:fd77a6b2f76c 14
mjr 38:091e511ce8a0 15 // Data Transmission Mode.
mjr 38:091e511ce8a0 16 //
mjr 38:091e511ce8a0 17 // NOTE! This section contains a possible workaround to try if you're
mjr 38:091e511ce8a0 18 // having data signal stability problems with your TLC5940 chips. If
mjr 40:cc0d9814522b 19 // things are working properly, you can ignore this part.
mjr 33:d832bcab089e 20 //
mjr 38:091e511ce8a0 21 // The software has two options for sending data updates to the chips:
mjr 38:091e511ce8a0 22 //
mjr 40:cc0d9814522b 23 // Mode 0: Send data *during* the grayscale cycle. This is the default,
mjr 40:cc0d9814522b 24 // and it's the standard method the chips are designed for. In this mode,
mjr 40:cc0d9814522b 25 // we start sending an update just after then blanking interval that starts
mjr 40:cc0d9814522b 26 // a new grayscale cycle. The timing is arranged so that the update is
mjr 40:cc0d9814522b 27 // completed well before the end of the grayscale cycle. At the next
mjr 40:cc0d9814522b 28 // blanking interval, we latch the new data, so the new brightness levels
mjr 40:cc0d9814522b 29 // will be shown starting on the next cycle.
mjr 40:cc0d9814522b 30
mjr 38:091e511ce8a0 31 // Mode 1: Send data *between* grayscale cycles. In this mode, we send
mjr 38:091e511ce8a0 32 // each complete update during a blanking period, then latch the update
mjr 38:091e511ce8a0 33 // and start the next grayscale cycle. This isn't the way the chips were
mjr 38:091e511ce8a0 34 // intended to be used, but it works. The disadvantage is that it requires
mjr 40:cc0d9814522b 35 // the blanking interval to be extended long enough for the full data
mjr 40:cc0d9814522b 36 // update (192 bits * the number of chips in the chain). Since the
mjr 40:cc0d9814522b 37 // outputs are turned off throughout the blanking period, this reduces
mjr 38:091e511ce8a0 38 // the overall brightness/intensity of the outputs by reducing the duty
mjr 38:091e511ce8a0 39 // cycle. The TLC5940 chips can't achieve 100% duty cycle to begin with,
mjr 40:cc0d9814522b 40 // since they require a brief minimum time in the blanking interval
mjr 38:091e511ce8a0 41 // between grayscale cycles; however, the minimum is so short that the
mjr 38:091e511ce8a0 42 // duty cycle is close to 100%. With the full data transmission stuffed
mjr 38:091e511ce8a0 43 // into the blanking interval, we reduce the duty cycle further below
mjr 38:091e511ce8a0 44 // 100%. With four chips in the chain, a 28 MHz data clock, and a
mjr 38:091e511ce8a0 45 // 500 kHz grayscale clock, the reduction is about 0.3%.
mjr 33:d832bcab089e 46 //
mjr 40:cc0d9814522b 47 // Mode 0 is the method documented in the manufacturer's data sheet.
mjr 40:cc0d9814522b 48 // It works well empirically with the Pinscape expansion boards.
mjr 40:cc0d9814522b 49 //
mjr 38:091e511ce8a0 50 // So what's the point of Mode 1? In early testing, with a breadboard
mjr 38:091e511ce8a0 51 // setup, I saw some problems with data signal stability, which manifested
mjr 38:091e511ce8a0 52 // as sporadic flickering in the outputs. Switching to Mode 1 improved
mjr 38:091e511ce8a0 53 // the signal stability considerably. I'm therefore leaving this code
mjr 38:091e511ce8a0 54 // available as an option in case anyone runs into similar signal problems
mjr 38:091e511ce8a0 55 // and wants to try the alternative mode as a workaround.
mjr 38:091e511ce8a0 56 //
mjr 38:091e511ce8a0 57 #define DATA_UPDATE_INSIDE_BLANKING 0
mjr 33:d832bcab089e 58
mjr 26:cb71c4af2912 59 #include "mbed.h"
mjr 30:6e9902f06f48 60 #include "SimpleDMA.h"
mjr 47:df7a88cd249c 61 #include "DMAChannels.h"
mjr 26:cb71c4af2912 62
mjr 54:fd77a6b2f76c 63
mjr 26:cb71c4af2912 64 /**
mjr 26:cb71c4af2912 65 * SPI speed used by the mbed to communicate with the TLC5940
mjr 26:cb71c4af2912 66 * The TLC5940 supports up to 30Mhz. It's best to keep this as
mjr 33:d832bcab089e 67 * high as possible, since a higher SPI speed yields a faster
mjr 33:d832bcab089e 68 * grayscale data update. However, I've seen some slight
mjr 33:d832bcab089e 69 * instability in the signal in my breadboard setup using the
mjr 33:d832bcab089e 70 * full 30MHz, so I've reduced this slightly, which seems to
mjr 33:d832bcab089e 71 * yield a solid signal. The limit will vary according to how
mjr 33:d832bcab089e 72 * clean the signal path is to the chips; you can probably crank
mjr 33:d832bcab089e 73 * this up to full speed if you have a well-designed PCB, good
mjr 33:d832bcab089e 74 * decoupling capacitors near the 5940 VCC/GND pins, and short
mjr 33:d832bcab089e 75 * wires between the KL25Z and the PCB. A short, clean path to
mjr 33:d832bcab089e 76 * KL25Z ground seems especially important.
mjr 26:cb71c4af2912 77 *
mjr 26:cb71c4af2912 78 * The SPI clock must be fast enough that the data transmission
mjr 26:cb71c4af2912 79 * time for a full update is comfortably less than the blanking
mjr 26:cb71c4af2912 80 * cycle time. The grayscale refresh requires 192 bits per TLC5940
mjr 26:cb71c4af2912 81 * in the daisy chain, and each bit takes one SPI clock to send.
mjr 26:cb71c4af2912 82 * Our reference setup in the Pinscape controller allows for up to
mjr 26:cb71c4af2912 83 * 4 TLC5940s, so a full refresh cycle on a fully populated system
mjr 26:cb71c4af2912 84 * would be 768 SPI clocks. The blanking cycle is 4096 GSCLK cycles.
mjr 26:cb71c4af2912 85 *
mjr 26:cb71c4af2912 86 * t(blank) = 4096 * 1/GSCLK_SPEED
mjr 26:cb71c4af2912 87 * t(refresh) = 768 * 1/SPI_SPEED
mjr 26:cb71c4af2912 88 * Therefore: SPI_SPEED must be > 768/4096 * GSCLK_SPEED
mjr 26:cb71c4af2912 89 *
mjr 26:cb71c4af2912 90 * Since the SPI speed can be so high, and since we want to keep
mjr 26:cb71c4af2912 91 * the GSCLK speed relatively low, the constraint above simply
mjr 26:cb71c4af2912 92 * isn't a factor. E.g., at SPI=30MHz and GSCLK=500kHz,
mjr 26:cb71c4af2912 93 * t(blank) is 8192us and t(refresh) is 25us.
mjr 26:cb71c4af2912 94 */
mjr 38:091e511ce8a0 95 #define SPI_SPEED 28000000
mjr 26:cb71c4af2912 96
mjr 26:cb71c4af2912 97 /**
mjr 26:cb71c4af2912 98 * The rate at which the GSCLK pin is pulsed. This also controls
mjr 26:cb71c4af2912 99 * how often the reset function is called. The reset function call
mjr 38:091e511ce8a0 100 * interval is (1/GSCLK_SPEED) * 4096. The maximum reliable rate is
mjr 26:cb71c4af2912 101 * around 32Mhz. It's best to keep this rate as low as possible:
mjr 26:cb71c4af2912 102 * the higher the rate, the higher the refresh() call frequency,
mjr 40:cc0d9814522b 103 * so the higher the CPU load. Higher frequencies also make it more
mjr 40:cc0d9814522b 104 * challenging to wire the chips for clean signal transmission, so
mjr 40:cc0d9814522b 105 * minimizing the clock speed will help with signal stability.
mjr 26:cb71c4af2912 106 *
mjr 40:cc0d9814522b 107 * The lower bound depends on the application. For driving lights,
mjr 40:cc0d9814522b 108 * the limiting factor is flicker: the lower the rate, the more
mjr 40:cc0d9814522b 109 * noticeable the flicker. Incandescents tend to look flicker-free
mjr 40:cc0d9814522b 110 * at about 50 Hz (205 kHz grayscale clock). LEDs need slightly
mjr 40:cc0d9814522b 111 * faster rates.
mjr 26:cb71c4af2912 112 */
mjr 40:cc0d9814522b 113 #define GSCLK_SPEED 350000
mjr 26:cb71c4af2912 114
mjr 26:cb71c4af2912 115 class TLC5940
mjr 26:cb71c4af2912 116 {
mjr 26:cb71c4af2912 117 public:
mjr 54:fd77a6b2f76c 118 uint64_t spi_total_time;//$$$
mjr 54:fd77a6b2f76c 119 uint32_t spi_runs;//$$$
mjr 54:fd77a6b2f76c 120
mjr 26:cb71c4af2912 121 /**
mjr 26:cb71c4af2912 122 * Set up the TLC5940
mjr 54:fd77a6b2f76c 123 *
mjr 26:cb71c4af2912 124 * @param SCLK - The SCK pin of the SPI bus
mjr 26:cb71c4af2912 125 * @param MOSI - The MOSI pin of the SPI bus
mjr 26:cb71c4af2912 126 * @param GSCLK - The GSCLK pin of the TLC5940(s)
mjr 26:cb71c4af2912 127 * @param BLANK - The BLANK pin of the TLC5940(s)
mjr 26:cb71c4af2912 128 * @param XLAT - The XLAT pin of the TLC5940(s)
mjr 26:cb71c4af2912 129 * @param nchips - The number of TLC5940s (if you are daisy chaining)
mjr 26:cb71c4af2912 130 */
mjr 26:cb71c4af2912 131 TLC5940(PinName SCLK, PinName MOSI, PinName GSCLK, PinName BLANK, PinName XLAT, int nchips)
mjr 47:df7a88cd249c 132 : sdma(DMAch_TLC5940),
mjr 47:df7a88cd249c 133 spi(MOSI, NC, SCLK),
mjr 26:cb71c4af2912 134 gsclk(GSCLK),
mjr 26:cb71c4af2912 135 blank(BLANK),
mjr 26:cb71c4af2912 136 xlat(XLAT),
mjr 33:d832bcab089e 137 nchips(nchips)
mjr 26:cb71c4af2912 138 {
mjr 54:fd77a6b2f76c 139 spi_total_time = 0; spi_runs = 0; // $$$
mjr 54:fd77a6b2f76c 140
mjr 40:cc0d9814522b 141 // start up initially disabled
mjr 40:cc0d9814522b 142 enabled = false;
mjr 40:cc0d9814522b 143
mjr 33:d832bcab089e 144 // set XLAT to initially off
mjr 30:6e9902f06f48 145 xlat = 0;
mjr 33:d832bcab089e 146
mjr 33:d832bcab089e 147 // Assert BLANK while starting up, to keep the outputs turned off until
mjr 33:d832bcab089e 148 // everything is stable. This helps prevent spurious flashes during startup.
mjr 33:d832bcab089e 149 // (That's not particularly important for lights, but it matters more for
mjr 33:d832bcab089e 150 // tactile devices. It's a bit alarming to fire a replay knocker on every
mjr 33:d832bcab089e 151 // power-on, for example.)
mjr 30:6e9902f06f48 152 blank = 1;
mjr 30:6e9902f06f48 153
mjr 26:cb71c4af2912 154 // Configure SPI format and speed. Note that KL25Z ONLY supports 8-bit
mjr 26:cb71c4af2912 155 // mode. The TLC5940 nominally requires 12-bit data blocks for the
mjr 26:cb71c4af2912 156 // grayscale levels, but SPI is ultimately just a bit-level serial format,
mjr 26:cb71c4af2912 157 // so we can reformat the 12-bit blocks into 8-bit bytes to fit the
mjr 26:cb71c4af2912 158 // KL25Z's limits. This should work equally well on other microcontrollers
mjr 38:091e511ce8a0 159 // that are more flexible. The TLC5940 requires polarity/phase format 0.
mjr 26:cb71c4af2912 160 spi.format(8, 0);
mjr 26:cb71c4af2912 161 spi.frequency(SPI_SPEED);
mjr 33:d832bcab089e 162
mjr 33:d832bcab089e 163 // Send out a full data set to the chips, to clear out any random
mjr 33:d832bcab089e 164 // startup data from the registers. Include some extra bits - there
mjr 33:d832bcab089e 165 // are some cases (such as after sending dot correct commands) where
mjr 33:d832bcab089e 166 // an extra bit per chip is required, and the initial state is
mjr 54:fd77a6b2f76c 167 // unpredictable, so send extra bits to make sure we cover all bases.
mjr 54:fd77a6b2f76c 168 // This does no harm; extra bits just fall off the end of the daisy
mjr 54:fd77a6b2f76c 169 // chain, and since we want all registers initially set to 0, we can
mjr 33:d832bcab089e 170 // send arbitrarily many extra 0's.
mjr 33:d832bcab089e 171 for (int i = 0 ; i < nchips*25 ; ++i)
mjr 54:fd77a6b2f76c 172 spi.write(0x00);
mjr 33:d832bcab089e 173
mjr 33:d832bcab089e 174 // do an initial XLAT to latch all of these "0" values into the
mjr 33:d832bcab089e 175 // grayscale registers
mjr 33:d832bcab089e 176 xlat = 1;
mjr 33:d832bcab089e 177 xlat = 0;
mjr 29:582472d0bc57 178
mjr 39:b3815a1c3802 179 // Allocate our DMA buffers. The transfer on each cycle is 192 bits per
mjr 40:cc0d9814522b 180 // chip = 24 bytes per chip. Allocate two buffers, so that we have a
mjr 40:cc0d9814522b 181 // stable buffer that we can send to the chips, and a separate working
mjr 40:cc0d9814522b 182 // copy that we can asynchronously update.
mjr 40:cc0d9814522b 183 dmalen = nchips*24;
mjr 48:058ace2aed1d 184 livebuf = new uint8_t[dmalen*2];
mjr 54:fd77a6b2f76c 185 memset(livebuf, 0x00, dmalen*2);
mjr 40:cc0d9814522b 186
mjr 40:cc0d9814522b 187 // start with buffer 0 live, with no new data pending
mjr 48:058ace2aed1d 188 workbuf = livebuf + dmalen;
mjr 40:cc0d9814522b 189 dirty = false;
mjr 40:cc0d9814522b 190
mjr 30:6e9902f06f48 191 // Set up the Simple DMA interface object. We use the DMA controller to
mjr 30:6e9902f06f48 192 // send grayscale data updates to the TLC5940 chips. This lets the CPU
mjr 30:6e9902f06f48 193 // keep running other tasks while we send gs updates, and importantly
mjr 30:6e9902f06f48 194 // allows our blanking interrupt handler return almost immediately.
mjr 30:6e9902f06f48 195 // The DMA transfer is from our internal DMA buffer to SPI0, which is
mjr 30:6e9902f06f48 196 // the SPI controller physically connected to the TLC5940s.
mjr 54:fd77a6b2f76c 197 SPI0->C2 &= ~SPI_C2_TXDMAE_MASK;
mjr 54:fd77a6b2f76c 198 sdma.attach(this, &TLC5940::dmaDone);
mjr 48:058ace2aed1d 199 sdma.destination(&SPI0->D, false, 8);
mjr 30:6e9902f06f48 200 sdma.trigger(Trigger_SPI0_TX);
mjr 30:6e9902f06f48 201
mjr 30:6e9902f06f48 202 // Configure the GSCLK output's frequency
mjr 26:cb71c4af2912 203 gsclk.period(1.0/GSCLK_SPEED);
mjr 33:d832bcab089e 204
mjr 33:d832bcab089e 205 // mark that we need an initial update
mjr 54:fd77a6b2f76c 206 forceUpdate = true;
mjr 33:d832bcab089e 207 needXlat = false;
mjr 40:cc0d9814522b 208 }
mjr 40:cc0d9814522b 209
mjr 40:cc0d9814522b 210 // Global enable/disble. When disabled, we assert the blanking signal
mjr 40:cc0d9814522b 211 // continuously to keep all outputs turned off. This can be used during
mjr 40:cc0d9814522b 212 // startup and sleep mode to prevent spurious output signals from
mjr 40:cc0d9814522b 213 // uninitialized grayscale registers. The chips have random values in
mjr 40:cc0d9814522b 214 // their internal registers when power is first applied, so we have to
mjr 40:cc0d9814522b 215 // explicitly send the initial zero levels after power cycling the chips.
mjr 40:cc0d9814522b 216 // The chips might not have power even when the KL25Z is running, because
mjr 40:cc0d9814522b 217 // they might be powered from a separate power supply from the KL25Z
mjr 40:cc0d9814522b 218 // (the Pinscape Expansion Boards work this way). Global blanking helps
mjr 40:cc0d9814522b 219 // us start up more cleanly by suppressing all outputs until we can be
mjr 40:cc0d9814522b 220 // reasonably sure that the various chip registers are initialized.
mjr 40:cc0d9814522b 221 void enable(bool f)
mjr 40:cc0d9814522b 222 {
mjr 40:cc0d9814522b 223 // note the new setting
mjr 40:cc0d9814522b 224 enabled = f;
mjr 40:cc0d9814522b 225
mjr 40:cc0d9814522b 226 // if disabled, apply blanking immediately
mjr 40:cc0d9814522b 227 if (!f)
mjr 40:cc0d9814522b 228 {
mjr 40:cc0d9814522b 229 gsclk.write(0);
mjr 40:cc0d9814522b 230 blank = 1;
mjr 40:cc0d9814522b 231 }
mjr 40:cc0d9814522b 232
mjr 40:cc0d9814522b 233 // do a full update with the new setting
mjr 54:fd77a6b2f76c 234 forceUpdate = true;
mjr 40:cc0d9814522b 235 }
mjr 29:582472d0bc57 236
mjr 30:6e9902f06f48 237 // Start the clock running
mjr 29:582472d0bc57 238 void start()
mjr 29:582472d0bc57 239 {
mjr 26:cb71c4af2912 240 // Set up the first call to the reset function, which asserts BLANK to
mjr 26:cb71c4af2912 241 // end the PWM cycle and handles new grayscale data output and latching.
mjr 26:cb71c4af2912 242 // The original version of this library uses a timer to call reset
mjr 26:cb71c4af2912 243 // periodically, but that approach is somewhat problematic because the
mjr 26:cb71c4af2912 244 // reset function itself takes a small amount of time to run, so the
mjr 26:cb71c4af2912 245 // *actual* cycle is slightly longer than what we get from counting
mjr 26:cb71c4af2912 246 // GS clocks. Running reset on a timer therefore causes the calls to
mjr 26:cb71c4af2912 247 // slip out of phase with the actual full cycles, which causes
mjr 26:cb71c4af2912 248 // premature blanking that shows up as visible flicker. To get the
mjr 54:fd77a6b2f76c 249 // reset cycle to line up more precisely with a full PWM cycle, it
mjr 54:fd77a6b2f76c 250 // works better to set up a new timer at the end of each cycle. That
mjr 54:fd77a6b2f76c 251 // organically accounts for the time spent in the interrupt handler.
mjr 54:fd77a6b2f76c 252 // This doesn't result in perfectly uniform timing, since interrupt
mjr 54:fd77a6b2f76c 253 // latency varies slightly on each interrupt, but it does guarantee
mjr 54:fd77a6b2f76c 254 // that the blanking will never be premature - all variation will go
mjr 54:fd77a6b2f76c 255 // into the tail end of the cycle after the 4096 GS clocks. That
mjr 54:fd77a6b2f76c 256 // might cause some brightness variation, but it won't cause flicker,
mjr 54:fd77a6b2f76c 257 // and in practice any brightness variation from this seems to be too
mjr 54:fd77a6b2f76c 258 // small to be visible.
mjr 54:fd77a6b2f76c 259 armReset();
mjr 26:cb71c4af2912 260 }
mjr 26:cb71c4af2912 261
mjr 39:b3815a1c3802 262 /*
mjr 39:b3815a1c3802 263 * Set an output
mjr 26:cb71c4af2912 264 */
mjr 26:cb71c4af2912 265 void set(int idx, unsigned short data)
mjr 26:cb71c4af2912 266 {
mjr 39:b3815a1c3802 267 // validate the index
mjr 39:b3815a1c3802 268 if (idx >= 0 && idx < nchips*16)
mjr 39:b3815a1c3802 269 {
mjr 40:cc0d9814522b 270 // If the buffer isn't dirty, it means that the previous working buffer
mjr 40:cc0d9814522b 271 // was swapped into the live buffer on the last blanking interval. This
mjr 40:cc0d9814522b 272 // means that the working buffer hasn't been updated to the live data yet,
mjr 40:cc0d9814522b 273 // so we need to copy it now.
mjr 54:fd77a6b2f76c 274 //
mjr 54:fd77a6b2f76c 275 // If 'dirty' is false, it can't change to true asynchronously - it can
mjr 54:fd77a6b2f76c 276 // only transition from false to true in application (non-ISR) context.
mjr 54:fd77a6b2f76c 277 // If it's true, though, the interrupt handler can change it to false
mjr 54:fd77a6b2f76c 278 // asynchronously, and can also swap the 'live' and 'work' buffer pointers.
mjr 54:fd77a6b2f76c 279 // This means we must do the whole update atomically if 'dirty' is true.
mjr 54:fd77a6b2f76c 280 __disable_irq();
mjr 40:cc0d9814522b 281 if (!dirty)
mjr 40:cc0d9814522b 282 {
mjr 54:fd77a6b2f76c 283 // Buffer is clean, so the interrupt handler won't touch 'dirty'
mjr 54:fd77a6b2f76c 284 // or the live/work buffer pointers. This means we can do the
mjr 54:fd77a6b2f76c 285 // rest of our work with interrupts on.
mjr 54:fd77a6b2f76c 286 __enable_irq();
mjr 54:fd77a6b2f76c 287
mjr 54:fd77a6b2f76c 288 // get the current live data into our work buffer
mjr 40:cc0d9814522b 289 memcpy(workbuf, livebuf, dmalen);
mjr 40:cc0d9814522b 290 }
mjr 40:cc0d9814522b 291
mjr 54:fd77a6b2f76c 292 // Figure the DMA buffer location of the output we're changing. The DMA
mjr 54:fd77a6b2f76c 293 // buffer has the packed bit format that we send across the wire, with 12
mjr 54:fd77a6b2f76c 294 // bits per output, arranged from last output to first output (N = number
mjr 54:fd77a6b2f76c 295 // of outputs = nchips*16):
mjr 39:b3815a1c3802 296 //
mjr 39:b3815a1c3802 297 // byte 0 = high 8 bits of output N-1
mjr 39:b3815a1c3802 298 // 1 = low 4 bits of output N-1 | high 4 bits of output N-2
mjr 39:b3815a1c3802 299 // 2 = low 8 bits of N-2
mjr 39:b3815a1c3802 300 // 3 = high 8 bits of N-3
mjr 39:b3815a1c3802 301 // 4 = low 4 bits of N-3 | high 4 bits of N-2
mjr 39:b3815a1c3802 302 // 5 = low 8bits of N-4
mjr 39:b3815a1c3802 303 // ...
mjr 39:b3815a1c3802 304 // 24*nchips-3 = high 8 bits of output 1
mjr 39:b3815a1c3802 305 // 24*nchips-2 = low 4 bits of output 1 | high 4 bits of output 0
mjr 39:b3815a1c3802 306 // 24*nchips-1 = low 8 bits of output 0
mjr 39:b3815a1c3802 307 //
mjr 39:b3815a1c3802 308 // So this update will affect two bytes. If the output number if even, we're
mjr 39:b3815a1c3802 309 // in the high 4 + low 8 pair; if odd, we're in the high 8 + low 4 pair.
mjr 39:b3815a1c3802 310 int di = nchips*24 - 3 - (3*(idx/2));
mjr 39:b3815a1c3802 311 if (idx & 1)
mjr 39:b3815a1c3802 312 {
mjr 39:b3815a1c3802 313 // ODD = high 8 | low 4
mjr 40:cc0d9814522b 314 workbuf[di] = uint8_t((data >> 4) & 0xff);
mjr 40:cc0d9814522b 315 workbuf[di+1] &= 0x0F;
mjr 40:cc0d9814522b 316 workbuf[di+1] |= uint8_t((data << 4) & 0xf0);
mjr 39:b3815a1c3802 317 }
mjr 39:b3815a1c3802 318 else
mjr 39:b3815a1c3802 319 {
mjr 39:b3815a1c3802 320 // EVEN = high 4 | low 8
mjr 40:cc0d9814522b 321 workbuf[di+1] &= 0xF0;
mjr 40:cc0d9814522b 322 workbuf[di+1] |= uint8_t((data >> 8) & 0x0f);
mjr 40:cc0d9814522b 323 workbuf[di+2] = uint8_t(data & 0xff);
mjr 39:b3815a1c3802 324 }
mjr 39:b3815a1c3802 325
mjr 54:fd77a6b2f76c 326 // if we weren't dirty before, we are now
mjr 54:fd77a6b2f76c 327 if (!dirty)
mjr 54:fd77a6b2f76c 328 {
mjr 54:fd77a6b2f76c 329 // we need an update
mjr 54:fd77a6b2f76c 330 dirty = true;
mjr 54:fd77a6b2f76c 331 }
mjr 54:fd77a6b2f76c 332 else
mjr 54:fd77a6b2f76c 333 {
mjr 54:fd77a6b2f76c 334 // The buffer was already dirty, so we had to write the buffer with
mjr 54:fd77a6b2f76c 335 // interrupts off. We're done, so we can re-enable interrupts now.
mjr 54:fd77a6b2f76c 336 __enable_irq();
mjr 54:fd77a6b2f76c 337 }
mjr 39:b3815a1c3802 338 }
mjr 26:cb71c4af2912 339 }
mjr 40:cc0d9814522b 340
mjr 40:cc0d9814522b 341 // Update the outputs. We automatically update the outputs on the grayscale timer
mjr 40:cc0d9814522b 342 // when we have pending changes, so it's not necessary to call this explicitly after
mjr 40:cc0d9814522b 343 // making a change via set(). This can be called to force an update when the chips
mjr 40:cc0d9814522b 344 // might be out of sync with our internal state, such as after power-on.
mjr 40:cc0d9814522b 345 void update(bool force = false)
mjr 40:cc0d9814522b 346 {
mjr 40:cc0d9814522b 347 if (force)
mjr 54:fd77a6b2f76c 348 forceUpdate = true;
mjr 40:cc0d9814522b 349 }
mjr 26:cb71c4af2912 350
mjr 26:cb71c4af2912 351 private:
mjr 26:cb71c4af2912 352 // current level for each output
mjr 26:cb71c4af2912 353 unsigned short *gs;
mjr 26:cb71c4af2912 354
mjr 30:6e9902f06f48 355 // Simple DMA interface object
mjr 30:6e9902f06f48 356 SimpleDMA sdma;
mjr 30:6e9902f06f48 357
mjr 40:cc0d9814522b 358 // DMA transfer buffers - double buffer. Each time we have data to transmit to the
mjr 40:cc0d9814522b 359 // TLC5940 chips, we format the data into the working half of this buffer exactly as
mjr 40:cc0d9814522b 360 // it will go across the wire, then hand the buffer to the DMA controller to move
mjr 40:cc0d9814522b 361 // through the SPI port. This memory block is actually two buffers, one live and
mjr 40:cc0d9814522b 362 // one pending. When we're ready to send updates to the chips, we swap the working
mjr 40:cc0d9814522b 363 // buffer into the live buffer so that we can send the latest updates. We keep a
mjr 40:cc0d9814522b 364 // separate working copy so that our live copy is stable, so that we don't alter
mjr 40:cc0d9814522b 365 // any data in the midst of an asynchronous DMA transmission to the chips.
mjr 48:058ace2aed1d 366 uint8_t *volatile livebuf;
mjr 48:058ace2aed1d 367 uint8_t *volatile workbuf;
mjr 40:cc0d9814522b 368
mjr 40:cc0d9814522b 369 // length of each DMA buffer, in bytes - 12 bits = 1.5 bytes per output, 16 outputs
mjr 40:cc0d9814522b 370 // per chip -> 24 bytes per chip
mjr 40:cc0d9814522b 371 uint16_t dmalen;
mjr 40:cc0d9814522b 372
mjr 40:cc0d9814522b 373 // Dirty: true means that the non-live buffer has new pending data. False means
mjr 40:cc0d9814522b 374 // that the non-live buffer is empty.
mjr 54:fd77a6b2f76c 375 volatile bool dirty;
mjr 54:fd77a6b2f76c 376
mjr 54:fd77a6b2f76c 377 // Force an update: true means that we'll send our GS data to the chips even if
mjr 54:fd77a6b2f76c 378 // the buffer isn't dirty.
mjr 54:fd77a6b2f76c 379 volatile bool forceUpdate;
mjr 40:cc0d9814522b 380
mjr 40:cc0d9814522b 381 // Enabled: this enables or disables all outputs. When this is true, we assert the
mjr 40:cc0d9814522b 382 // BLANK signal continuously.
mjr 40:cc0d9814522b 383 bool enabled;
mjr 30:6e9902f06f48 384
mjr 26:cb71c4af2912 385 // SPI port - only MOSI and SCK are used
mjr 26:cb71c4af2912 386 SPI spi;
mjr 26:cb71c4af2912 387
mjr 26:cb71c4af2912 388 // use a PWM out for the grayscale clock - this provides a stable
mjr 26:cb71c4af2912 389 // square wave signal without consuming CPU
mjr 54:fd77a6b2f76c 390 FastPWM gsclk;
mjr 26:cb71c4af2912 391
mjr 26:cb71c4af2912 392 // Digital out pins used for the TLC5940
mjr 26:cb71c4af2912 393 DigitalOut blank;
mjr 26:cb71c4af2912 394 DigitalOut xlat;
mjr 26:cb71c4af2912 395
mjr 26:cb71c4af2912 396 // number of daisy-chained TLC5940s we're controlling
mjr 26:cb71c4af2912 397 int nchips;
mjr 26:cb71c4af2912 398
mjr 26:cb71c4af2912 399 // Timeout to end each PWM cycle. This is a one-shot timer that we reset
mjr 26:cb71c4af2912 400 // on each cycle.
mjr 38:091e511ce8a0 401 Timeout resetTimer;
mjr 26:cb71c4af2912 402
mjr 33:d832bcab089e 403 // Do we need an XLAT signal on the next blanking interval?
mjr 33:d832bcab089e 404 volatile bool needXlat;
mjr 54:fd77a6b2f76c 405
mjr 40:cc0d9814522b 406 // Reset the grayscale cycle and send the next data update
mjr 26:cb71c4af2912 407 void reset()
mjr 26:cb71c4af2912 408 {
mjr 30:6e9902f06f48 409 // start the blanking cycle
mjr 30:6e9902f06f48 410 startBlank();
mjr 33:d832bcab089e 411
mjr 54:fd77a6b2f76c 412 #if !DATA_UPDATE_INSIDE_BLANKING
mjr 48:058ace2aed1d 413 // We're configured to send new GS data during the GS cycle,
mjr 48:058ace2aed1d 414 // not during the blanking interval, so end the blanking
mjr 48:058ace2aed1d 415 // interval now, before we start sending the new data. Ending
mjr 48:058ace2aed1d 416 // the blanking interval starts the new GS cycle.
mjr 33:d832bcab089e 417 //
mjr 48:058ace2aed1d 418 // (For the other configuration, we send GS data during the
mjr 48:058ace2aed1d 419 // blanking interval, so in that case we DON'T end the blanking
mjr 48:058ace2aed1d 420 // interval yet - we defer that until the end-of-DMA interrupt
mjr 48:058ace2aed1d 421 // handler, which fires after the GS data send has completed.)
mjr 33:d832bcab089e 422 endBlank();
mjr 48:058ace2aed1d 423 #endif
mjr 48:058ace2aed1d 424
mjr 54:fd77a6b2f76c 425 // if we have pending grayscale data, update the DMA data
mjr 54:fd77a6b2f76c 426 bool sendGS = true; // $$$
mjr 54:fd77a6b2f76c 427 if (dirty)
mjr 54:fd77a6b2f76c 428 {
mjr 54:fd77a6b2f76c 429 // The working buffer has changes since our last update. Swap
mjr 54:fd77a6b2f76c 430 // the live and working buffers so that we send the latest updates.
mjr 54:fd77a6b2f76c 431 uint8_t *tmp = livebuf;
mjr 54:fd77a6b2f76c 432 livebuf = workbuf;
mjr 54:fd77a6b2f76c 433 workbuf = tmp;
mjr 54:fd77a6b2f76c 434
mjr 54:fd77a6b2f76c 435 // the working buffer is no longer dirty
mjr 54:fd77a6b2f76c 436 dirty = false;
mjr 54:fd77a6b2f76c 437 sendGS = true;
mjr 54:fd77a6b2f76c 438 }
mjr 54:fd77a6b2f76c 439 else if (forceUpdate)
mjr 54:fd77a6b2f76c 440 {
mjr 54:fd77a6b2f76c 441 // send the GS data and consume the forced update flag
mjr 54:fd77a6b2f76c 442 sendGS = true;
mjr 54:fd77a6b2f76c 443 forceUpdate = false;
mjr 54:fd77a6b2f76c 444 }
mjr 54:fd77a6b2f76c 445
mjr 54:fd77a6b2f76c 446 // Set the new DMA source to the live buffer. Note that we start
mjr 54:fd77a6b2f76c 447 // the DMA transfer with the *second* byte - the first byte must
mjr 54:fd77a6b2f76c 448 // be sent by the CPU rather than the DMA module, as outlined in
mjr 54:fd77a6b2f76c 449 // the KL25Z hardware reference manual.
mjr 54:fd77a6b2f76c 450
mjr 54:fd77a6b2f76c 451 // Start the new DMA transfer.
mjr 54:fd77a6b2f76c 452 //
mjr 54:fd77a6b2f76c 453 // The hardware reference manual says that the CPU has to send
mjr 54:fd77a6b2f76c 454 // the first byte of a DMA transfer explicitly. This is required
mjr 54:fd77a6b2f76c 455 // to avoid a hardware deadlock condition that happens due to
mjr 54:fd77a6b2f76c 456 // a timing interaction between the SPI and DMA controllers.
mjr 54:fd77a6b2f76c 457 // The correct sequence per the manual is:
mjr 54:fd77a6b2f76c 458 //
mjr 54:fd77a6b2f76c 459 // - reset the SPI controller
mjr 54:fd77a6b2f76c 460 // - set up the DMA registers, starting at the 2nd byte to send
mjr 54:fd77a6b2f76c 461 // - read the SPI status register (SPI0->S), wait for SPTEF to be set
mjr 54:fd77a6b2f76c 462 // - write the first byte to the SPI data register (SPI0->D)
mjr 54:fd77a6b2f76c 463 // - enable TXDMAE in the SPI control register (SPI0->C2)
mjr 54:fd77a6b2f76c 464 //
mjr 54:fd77a6b2f76c 465 if (sendGS)
mjr 48:058ace2aed1d 466 {
mjr 54:fd77a6b2f76c 467 #if 1 // $$$
mjr 54:fd77a6b2f76c 468 Timer t; t.start(); //$$$
mjr 54:fd77a6b2f76c 469 uint8_t *p = livebuf;
mjr 54:fd77a6b2f76c 470 for (int i = dmalen ; i != 0 ; --i) {
mjr 54:fd77a6b2f76c 471 while (!(SPI0->S & SPI_S_SPTEF_MASK)) ;
mjr 54:fd77a6b2f76c 472 SPI0->D = *p++;
mjr 54:fd77a6b2f76c 473 }
mjr 54:fd77a6b2f76c 474 needXlat = true;
mjr 54:fd77a6b2f76c 475
mjr 54:fd77a6b2f76c 476 spi_total_time += t.read_us();
mjr 54:fd77a6b2f76c 477 spi_runs += 1;
mjr 54:fd77a6b2f76c 478 #else
mjr 54:fd77a6b2f76c 479 // disable DMA on SPI0
mjr 54:fd77a6b2f76c 480 SPI0->C2 &= ~SPI_C2_TXDMAE_MASK;
mjr 54:fd77a6b2f76c 481
mjr 54:fd77a6b2f76c 482 // reset SPI0
mjr 54:fd77a6b2f76c 483 SPI0->C1 &= ~SPI_C1_SPE_MASK;
mjr 54:fd77a6b2f76c 484
mjr 54:fd77a6b2f76c 485 // set up a transfer from the second byte of the buffer
mjr 54:fd77a6b2f76c 486 sdma.source(livebuf + 1, true, 8);
mjr 54:fd77a6b2f76c 487 sdma.start(dmalen - 1, false);
mjr 54:fd77a6b2f76c 488
mjr 54:fd77a6b2f76c 489 // enable SPI0
mjr 54:fd77a6b2f76c 490 SPI0->C1 |= SPI_C1_SPE_MASK;
mjr 54:fd77a6b2f76c 491
mjr 54:fd77a6b2f76c 492 // wait for the TX buffer to clear, then write the first byte manually
mjr 54:fd77a6b2f76c 493 while (!(SPI0->S & SPI_S_SPTEF_MASK)) ;
mjr 54:fd77a6b2f76c 494 SPI0->D = livebuf[0];
mjr 54:fd77a6b2f76c 495
mjr 54:fd77a6b2f76c 496 // enable DMA to carry out the rest of the transfer
mjr 48:058ace2aed1d 497 SPI0->C2 |= SPI_C2_TXDMAE_MASK;
mjr 54:fd77a6b2f76c 498
mjr 54:fd77a6b2f76c 499 // we'll need a translate on the next blanking cycle
mjr 54:fd77a6b2f76c 500 needXlat = true;
mjr 54:fd77a6b2f76c 501 #endif
mjr 48:058ace2aed1d 502 }
mjr 54:fd77a6b2f76c 503
mjr 54:fd77a6b2f76c 504 #if !DATA_UPDATE_INSIDE_BLANKING
mjr 54:fd77a6b2f76c 505 // arm the reset handler
mjr 54:fd77a6b2f76c 506 armReset();
mjr 54:fd77a6b2f76c 507 #endif
mjr 54:fd77a6b2f76c 508 }
mjr 54:fd77a6b2f76c 509
mjr 54:fd77a6b2f76c 510 // arm the reset handler - this fires at the end of each GS cycle
mjr 54:fd77a6b2f76c 511 void armReset()
mjr 54:fd77a6b2f76c 512 {
mjr 54:fd77a6b2f76c 513 resetTimer.attach(this, &TLC5940::reset, (1.0/GSCLK_SPEED)*4096.0);
mjr 30:6e9902f06f48 514 }
mjr 30:6e9902f06f48 515
mjr 30:6e9902f06f48 516 void startBlank()
mjr 30:6e9902f06f48 517 {
mjr 54:fd77a6b2f76c 518 //static int i=0; i=(i+1)%200; extern void diagLED(int,int,int); diagLED(i<100,i>=100,0);//$$$
mjr 54:fd77a6b2f76c 519
mjr 30:6e9902f06f48 520 // turn off the grayscale clock, and assert BLANK to end the grayscale cycle
mjr 30:6e9902f06f48 521 gsclk.write(0);
mjr 54:fd77a6b2f76c 522 blank = (enabled ? 1 : 0); // for the slight delay (20ns) required after GSCLK goes low
mjr 30:6e9902f06f48 523 blank = 1;
mjr 30:6e9902f06f48 524 }
mjr 26:cb71c4af2912 525
mjr 33:d832bcab089e 526 void endBlank()
mjr 30:6e9902f06f48 527 {
mjr 54:fd77a6b2f76c 528 //static int i=0; i=(i+1)%200; extern void diagLED(int,int,int); diagLED(-1,i<100,-1);//$$$
mjr 54:fd77a6b2f76c 529
mjr 33:d832bcab089e 530 // if we've sent new grayscale data since the last blanking
mjr 33:d832bcab089e 531 // interval, latch it by asserting XLAT
mjr 33:d832bcab089e 532 if (needXlat)
mjr 30:6e9902f06f48 533 {
mjr 26:cb71c4af2912 534 // latch the new data while we're still blanked
mjr 26:cb71c4af2912 535 xlat = 1;
mjr 26:cb71c4af2912 536 xlat = 0;
mjr 33:d832bcab089e 537 needXlat = false;
mjr 26:cb71c4af2912 538 }
mjr 26:cb71c4af2912 539
mjr 40:cc0d9814522b 540 // End the blanking interval and restart the grayscale clock. Note
mjr 40:cc0d9814522b 541 // that we keep the blanking on if the chips are globally disabled.
mjr 54:fd77a6b2f76c 542 if (enabled)
mjr 54:fd77a6b2f76c 543 {
mjr 54:fd77a6b2f76c 544 blank = 0;
mjr 54:fd77a6b2f76c 545 gsclk.write(.5);
mjr 54:fd77a6b2f76c 546 }
mjr 26:cb71c4af2912 547 }
mjr 26:cb71c4af2912 548
mjr 30:6e9902f06f48 549 // Interrupt handler for DMA completion. The DMA controller calls this
mjr 30:6e9902f06f48 550 // when it finishes with the transfer request we set up above. When the
mjr 30:6e9902f06f48 551 // transfer is done, we simply end the blanking cycle and start a new
mjr 30:6e9902f06f48 552 // grayscale cycle.
mjr 30:6e9902f06f48 553 void dmaDone()
mjr 30:6e9902f06f48 554 {
mjr 54:fd77a6b2f76c 555 //static int i=0; i=(i+1)%200; extern void diagLED(int,int,int); diagLED(i<100,-1,-1);//$$$
mjr 54:fd77a6b2f76c 556
mjr 48:058ace2aed1d 557 // disable DMA triggering in the SPI controller until we set
mjr 48:058ace2aed1d 558 // up the next transfer
mjr 48:058ace2aed1d 559 SPI0->C2 &= ~SPI_C2_TXDMAE_MASK;
mjr 54:fd77a6b2f76c 560 SPI0->C1 &= ~SPI_C1_SPE_MASK;
mjr 48:058ace2aed1d 561
mjr 33:d832bcab089e 562 // mark that we need to assert XLAT to latch the new
mjr 33:d832bcab089e 563 // grayscale data during the next blanking interval
mjr 54:fd77a6b2f76c 564 needXlat = true;
mjr 33:d832bcab089e 565
mjr 33:d832bcab089e 566 #if DATA_UPDATE_INSIDE_BLANKING
mjr 33:d832bcab089e 567 // we're doing the gs update within the blanking cycle, so end
mjr 33:d832bcab089e 568 // the blanking cycle now that the transfer has completed
mjr 33:d832bcab089e 569 endBlank();
mjr 54:fd77a6b2f76c 570
mjr 54:fd77a6b2f76c 571 // set up the next blanking interrupt
mjr 54:fd77a6b2f76c 572 armReset();
mjr 33:d832bcab089e 573 #endif
mjr 30:6e9902f06f48 574 }
mjr 30:6e9902f06f48 575
mjr 26:cb71c4af2912 576 };
mjr 26:cb71c4af2912 577
mjr 26:cb71c4af2912 578 #endif