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

/media/uploads/mjr/pinscape_no_background_small_L7Miwr6.jpg

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 mechanical plunger, button inputs, and feedback device control.

In case you haven't heard of the idea 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 show the backglass artwork. Some cabs also include a third monitor to simulate the DMD (Dot Matrix Display) used for scoring on 1990s machines, or even an original plasma DMD. A computer (usually a Windows PC) 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 trim hardware.

It's possible to buy a pre-built virtual pinball machine, but it also makes a great 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 vpforums.org. Also visit my Pinscape Resources page for more about this project and other virtual pinball projects I'm working on.

Downloads

  • 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.

Documentation

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 potentiometer (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 mouser.com 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 Aliexpress.com 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 KL25Z can only run one firmware program at a time, so if you install the Pinscape firmware on your KL25Z, it will replace and erase your existing VirtuaPin proprietary firmware. If you do this, the only way to restore your VirtuaPin firmware is to physically ship the KL25Z back to VirtuaPin and ask them to re-flash it. They don't allow you to do this at home, and they don't even allow you to back up your firmware, since they want to protect their proprietary software from copying. For all of these reasons, if you want to run the Pinscape software, I strongly recommend that you buy a "blank" retail KL25Z to use with Pinscape. They only cost about $15 and are available at several online retailers, including Amazon, Mouser, and eBay. The blank retail boards don't come with any proprietary firmware pre-installed, so installing Pinscape won't delete anything that you paid extra for.

With those warnings in mind, if you're absolutely sure that you don't mind permanently erasing your VirtuaPin firmware, it is at least possible to use Pinscape as a replacement for the VirtuaPin firmware. Pinscape uses the same button wiring conventions as the VirtuaPin setup, so you can keep your buttons (although you'll have to update the GPIO pin mappings in the Config Tool to match your physical wiring). As of the June, 2021 firmware, the Vishay VCNL4010 plunger sensor that comes with the VirtuaPin v3 plunger kit is supported, so you can also keep your plunger, if you have that chip. (You should check to be sure that's the sensor chip you have before committing to this route, if keeping the plunger sensor is important to you. The older VirtuaPin plunger kits came with different IR sensors that the Pinscape software doesn't handle.)

Committer:
mjr
Date:
Sat Apr 18 19:08:55 2020 +0000
Revision:
109:310ac82cbbee
Parent:
40:cc0d9814522b
TCD1103 DMA setup time padding to fix sporadic missed first pixel in transfer; fix TV ON so that the TV ON IR commands don't have to be grouped in the IR command first slots

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mjr 34:6b981a2afab7 1 /* Copyright 2014 M J Roberts, MIT License
mjr 34:6b981a2afab7 2 *
mjr 34:6b981a2afab7 3 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
mjr 34:6b981a2afab7 4 * and associated documentation files (the "Software"), to deal in the Software without
mjr 34:6b981a2afab7 5 * restriction, including without limitation the rights to use, copy, modify, merge, publish,
mjr 34:6b981a2afab7 6 * distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the
mjr 34:6b981a2afab7 7 * Software is furnished to do so, subject to the following conditions:
mjr 34:6b981a2afab7 8 *
mjr 34:6b981a2afab7 9 * The above copyright notice and this permission notice shall be included in all copies or
mjr 34:6b981a2afab7 10 * substantial portions of the Software.
mjr 34:6b981a2afab7 11 *
mjr 34:6b981a2afab7 12 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
mjr 34:6b981a2afab7 13 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
mjr 34:6b981a2afab7 14 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
mjr 34:6b981a2afab7 15 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
mjr 34:6b981a2afab7 16 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
mjr 34:6b981a2afab7 17 */
mjr 34:6b981a2afab7 18
mjr 34:6b981a2afab7 19 #ifndef HC595_INCLUDED
mjr 34:6b981a2afab7 20 #define HC595_INCLUDED
mjr 34:6b981a2afab7 21
mjr 34:6b981a2afab7 22 #include "mbed.h"
mjr 34:6b981a2afab7 23
mjr 34:6b981a2afab7 24 // 74HC595 Interface
mjr 34:6b981a2afab7 25 //
mjr 34:6b981a2afab7 26 // We require four GPIO pins:
mjr 34:6b981a2afab7 27 //
mjr 34:6b981a2afab7 28 // sin - serial data
mjr 34:6b981a2afab7 29 // sclk - serial clock
mjr 34:6b981a2afab7 30 // latch - the LATCH signal, which transfers the internal shift register
mjr 34:6b981a2afab7 31 // bits to the physical output pin states
mjr 34:6b981a2afab7 32 // ena - the Enable signal
mjr 34:6b981a2afab7 33 //
mjr 34:6b981a2afab7 34 // Note that the physical !OE (output enable) pin on the 74HC595 is active-low.
mjr 34:6b981a2afab7 35 // To allow for orderly startup that guarantees that outputs won't be pulsed
mjr 34:6b981a2afab7 36 // (even briefly) during power-on, we require the !OE pin to be wired with a
mjr 34:6b981a2afab7 37 // pull-up resistor to Vcc, and connected to our ENA GPIO pin via an inverter.
mjr 34:6b981a2afab7 38 //
mjr 34:6b981a2afab7 39 // Recommended wiring: connect the GPIO pin to the base of an NPN transistor
mjr 34:6b981a2afab7 40 // through a 2.2K resistor, connect the collector the !OE pin on the 74HC595,
mjr 34:6b981a2afab7 41 // and connect the emitter to ground. This will pull !OE to ground when we
mjr 34:6b981a2afab7 42 // write a digital 1 to the ENA GPIO, enabling the outputs.
mjr 34:6b981a2afab7 43 //
mjr 34:6b981a2afab7 44 // We use simple bit-banging through plain DigitalOut pins to send serial
mjr 34:6b981a2afab7 45 // data to the chips. This is fast enough for our purposes, since we send
mjr 34:6b981a2afab7 46 // only 8 bits per chip on each update (about 4us per chip per update), and
mjr 34:6b981a2afab7 47 // we only update when we get a command from the PC host that changes an
mjr 34:6b981a2afab7 48 // output state. These updates are at USB speed, so the update interval is
mjr 34:6b981a2afab7 49 // extremely long compared to the bit-banging time. If we wanted to use
mjr 34:6b981a2afab7 50 // these chips to implement PWM controlled by the microcontroller, or we
mjr 34:6b981a2afab7 51 // simply wanted to use a very long daisy-chain, we'd probably have to use
mjr 34:6b981a2afab7 52 // a faster transfer mechanism, such as the SPIO controller.
mjr 34:6b981a2afab7 53
mjr 34:6b981a2afab7 54 class HC595
mjr 34:6b981a2afab7 55 {
mjr 34:6b981a2afab7 56 public:
mjr 34:6b981a2afab7 57 HC595(int nchips, PinName sin, PinName sclk, PinName latch, PinName ena) :
mjr 34:6b981a2afab7 58 nchips(nchips), sin(sin), sclk(sclk), latch(latch), ena(ena)
mjr 34:6b981a2afab7 59 {
mjr 34:6b981a2afab7 60 // turn off all pins initially
mjr 34:6b981a2afab7 61 this->sin = 0;
mjr 34:6b981a2afab7 62 this->sclk = 0;
mjr 34:6b981a2afab7 63 this->latch = 0;
mjr 34:6b981a2afab7 64 this->ena = 0;
mjr 34:6b981a2afab7 65
mjr 34:6b981a2afab7 66 // allocate the state array
mjr 34:6b981a2afab7 67 state = new char[nchips*8];
mjr 34:6b981a2afab7 68 memset(state, 0, nchips*8);
mjr 34:6b981a2afab7 69 dirty = false;
mjr 34:6b981a2afab7 70 }
mjr 34:6b981a2afab7 71
mjr 34:6b981a2afab7 72 // Initialize. This must be called once at startup to clear the chips'
mjr 40:cc0d9814522b 73 // shift registers. We clock a 0 bit (OFF state) to each shift register
mjr 40:cc0d9814522b 74 // position and latch the OFF states on the outputs. Note that this
mjr 40:cc0d9814522b 75 // doesn't enable the chips - that must be done with a separate call
mjr 40:cc0d9814522b 76 // to enable(true).
mjr 34:6b981a2afab7 77 void init()
mjr 34:6b981a2afab7 78 {
mjr 34:6b981a2afab7 79 // set the internal state of all inputs
mjr 34:6b981a2afab7 80 memset(state, 0, nchips*8);
mjr 34:6b981a2afab7 81 dirty = false;
mjr 34:6b981a2afab7 82
mjr 34:6b981a2afab7 83 // clock a 0 to each shift register bit (8 per chip)
mjr 34:6b981a2afab7 84 sin = 0;
mjr 34:6b981a2afab7 85 for (int i = 0 ; i < nchips*8 ; ++i)
mjr 34:6b981a2afab7 86 {
mjr 34:6b981a2afab7 87 sclk = 1;
mjr 34:6b981a2afab7 88 sclk = 0;
mjr 34:6b981a2afab7 89 }
mjr 34:6b981a2afab7 90
mjr 34:6b981a2afab7 91 // latch the output data (this transfers the serial data register
mjr 34:6b981a2afab7 92 // bit for each pin to the actual output pin)
mjr 34:6b981a2afab7 93 latch = 1;
mjr 34:6b981a2afab7 94 latch = 0;
mjr 34:6b981a2afab7 95 }
mjr 34:6b981a2afab7 96
mjr 34:6b981a2afab7 97 // Set an output state. This only sets the state internally; call
mjr 34:6b981a2afab7 98 // update() to apply changes to the physical outputs.
mjr 34:6b981a2afab7 99 void set(int idx, int val)
mjr 34:6b981a2afab7 100 {
mjr 34:6b981a2afab7 101 if (state[idx] != val)
mjr 34:6b981a2afab7 102 {
mjr 34:6b981a2afab7 103 state[idx] = val;
mjr 34:6b981a2afab7 104 dirty = true;
mjr 34:6b981a2afab7 105 }
mjr 34:6b981a2afab7 106 }
mjr 34:6b981a2afab7 107
mjr 40:cc0d9814522b 108 // Global enable/disable the outputs. We use this for cleaner startup,
mjr 40:cc0d9814522b 109 // by disabling all outputs after power-on and when coming out of sleep
mjr 40:cc0d9814522b 110 // mode until we've had a chance to initialize the chip registers. The
mjr 40:cc0d9814522b 111 // chips have random values in their shift registers when first powered
mjr 40:cc0d9814522b 112 // on, so we have to send an initial update after power-on. The snag
mjr 40:cc0d9814522b 113 // is that the chips might have a separate power supply from the KL25Z,
mjr 40:cc0d9814522b 114 // so we can't assume that the chips are powered just because the program
mjr 40:cc0d9814522b 115 // is running. Instead, we can use the USB connection status as a proxy
mjr 40:cc0d9814522b 116 // for chip power, on the assumption that (a) the chips are running off
mjr 40:cc0d9814522b 117 // of the PC power supply, and (b) the USB connection can only be running
mjr 40:cc0d9814522b 118 // when the PC is running (hence the PC power supply is on).
mjr 40:cc0d9814522b 119 void enable(bool f)
mjr 40:cc0d9814522b 120 {
mjr 40:cc0d9814522b 121 // set the new enable state
mjr 40:cc0d9814522b 122 ena = (f ? 1 : 0);
mjr 40:cc0d9814522b 123 }
mjr 40:cc0d9814522b 124
mjr 34:6b981a2afab7 125 // Apply updates. This sends the current state of each pin to the
mjr 40:cc0d9814522b 126 // chips and latches the new settings. If 'force' is true, we flush
mjr 40:cc0d9814522b 127 // our internal state to the chips even if we haven't made any changes
mjr 40:cc0d9814522b 128 // since the last update.
mjr 40:cc0d9814522b 129 void update(bool force = false)
mjr 34:6b981a2afab7 130 {
mjr 40:cc0d9814522b 131 // if we have changes to apply, or the caller wants the update to
mjr 40:cc0d9814522b 132 // happen regardless of pending changes, refresh the chips
mjr 40:cc0d9814522b 133 if (dirty || force)
mjr 34:6b981a2afab7 134 {
mjr 34:6b981a2afab7 135 // Clock out the new states. Since the outputs are arranged
mjr 34:6b981a2afab7 136 // as shift registers, we have to clock out the bits in reverse
mjr 34:6b981a2afab7 137 // order of port numbers - the first bit we output will end up
mjr 34:6b981a2afab7 138 // in the last register after we clock out all of the other bits.
mjr 34:6b981a2afab7 139 // So clock out the last bit first and the first bit last.
mjr 34:6b981a2afab7 140 for (int i = nchips*8-1 ; i >= 0 ; --i)
mjr 34:6b981a2afab7 141 {
mjr 34:6b981a2afab7 142 sclk = 0;
mjr 34:6b981a2afab7 143 sin = state[i];
mjr 34:6b981a2afab7 144 sclk = 1;
mjr 34:6b981a2afab7 145 }
mjr 34:6b981a2afab7 146
mjr 34:6b981a2afab7 147 // latch the new states
mjr 34:6b981a2afab7 148 latch = 1;
mjr 34:6b981a2afab7 149 sclk = 0;
mjr 34:6b981a2afab7 150 latch = 0;
mjr 34:6b981a2afab7 151
mjr 34:6b981a2afab7 152 // outputs now reflect internal state
mjr 34:6b981a2afab7 153 dirty = false;
mjr 34:6b981a2afab7 154 }
mjr 34:6b981a2afab7 155 }
mjr 34:6b981a2afab7 156
mjr 34:6b981a2afab7 157
mjr 34:6b981a2afab7 158 private:
mjr 34:6b981a2afab7 159 int nchips; // number of chips in daisy chain
mjr 34:6b981a2afab7 160 bool dirty; // do we have changes to send to the chips?
mjr 34:6b981a2afab7 161 DigitalOut sin; // serial data pin
mjr 34:6b981a2afab7 162 DigitalOut sclk; // serial clock pin
mjr 34:6b981a2afab7 163 DigitalOut latch; // latch pin
mjr 34:6b981a2afab7 164 DigitalOut ena; // enable pin
mjr 34:6b981a2afab7 165 char *state; // array of current output states (0=off, 1=on)
mjr 34:6b981a2afab7 166 };
mjr 34:6b981a2afab7 167
mjr 34:6b981a2afab7 168 #endif // HC595_INCLUDED