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 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 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 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 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 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.

Committer:
mjr
Date:
Thu Apr 13 23:20:28 2017 +0000
Revision:
82:4f6209cb5c33
Child:
86:e30a1f60f783
Plunger refactoring; AEDR-8300 added; TSL1401CL in progress; VL6180X added

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mjr 82:4f6209cb5c33 1 // Bit Bang BitBangI2C implementation
mjr 82:4f6209cb5c33 2 //
mjr 82:4f6209cb5c33 3 // This implements an I2C interface that can operate on any GPIO ports,
mjr 82:4f6209cb5c33 4 // whether or not connected to I2C hardware on the MCU. We simply send
mjr 82:4f6209cb5c33 5 // and receive bits using DigitalInOut ports instead of MCU I2C hardware.
mjr 82:4f6209cb5c33 6 //
mjr 82:4f6209cb5c33 7 // Electrically, the I2C bus is designed as a a pair of open-collector
mjr 82:4f6209cb5c33 8 // lines with pull-up resistors. Any device can pull a line low by
mjr 82:4f6209cb5c33 9 // shorting it to ground, but no one can pull a line high: instead, you
mjr 82:4f6209cb5c33 10 // *allow* a line to go high by releasing it, which is to say putting
mjr 82:4f6209cb5c33 11 // your connection to it in a high-Z state. On an MCU, we put a GPIO
mjr 82:4f6209cb5c33 12 // in in high-Z state by setting its direction to INPUT mode. So our
mjr 82:4f6209cb5c33 13 // GPIO write strategy is like this:
mjr 82:4f6209cb5c33 14 //
mjr 82:4f6209cb5c33 15 // - take a pin low (0):
mjr 82:4f6209cb5c33 16 // pin.input();
mjr 82:4f6209cb5c33 17 // pin.write(0);
mjr 82:4f6209cb5c33 18 //
mjr 82:4f6209cb5c33 19 // - take a pin high (1):
mjr 82:4f6209cb5c33 20 // pin.output();
mjr 82:4f6209cb5c33 21 //
mjr 82:4f6209cb5c33 22
mjr 82:4f6209cb5c33 23 #include "mbed.h"
mjr 82:4f6209cb5c33 24 #include "BitBangI2C.h"
mjr 82:4f6209cb5c33 25
mjr 82:4f6209cb5c33 26 // --------------------------------------------------------------------------
mjr 82:4f6209cb5c33 27 //
mjr 82:4f6209cb5c33 28 // Debugging:
mjr 82:4f6209cb5c33 29 //
mjr 82:4f6209cb5c33 30 // 0 -> no debugging
mjr 82:4f6209cb5c33 31 // 1 -> print (on console) error messages only
mjr 82:4f6209cb5c33 32 // 2 -> print full diagnostics
mjr 82:4f6209cb5c33 33 //
mjr 82:4f6209cb5c33 34 // dprintf() = general debug diagnostics (printed only in case 2)
mjr 82:4f6209cb5c33 35 // eprintf() = error diagnostics (printed in case 1 and above)
mjr 82:4f6209cb5c33 36 //
mjr 82:4f6209cb5c33 37 #define BBI2C_DEBUG 1
mjr 82:4f6209cb5c33 38 #if BBI2C_DEBUG
mjr 82:4f6209cb5c33 39 # define eprintf(...) printf(__VA_ARGS__)
mjr 82:4f6209cb5c33 40 # if BBI2C_DEBUG >= 2
mjr 82:4f6209cb5c33 41 # define dprintf(...) printf(__VA_ARGS__)
mjr 82:4f6209cb5c33 42 # else
mjr 82:4f6209cb5c33 43 # define dprintf(...)
mjr 82:4f6209cb5c33 44 # endif
mjr 82:4f6209cb5c33 45 static const char *dbgbytes(const uint8_t *bytes, size_t len)
mjr 82:4f6209cb5c33 46 {
mjr 82:4f6209cb5c33 47 static char buf[128];
mjr 82:4f6209cb5c33 48 char *p = buf;
mjr 82:4f6209cb5c33 49 for (int i = 0 ; i < len && p + 4 < buf + sizeof(buf) ; ++i)
mjr 82:4f6209cb5c33 50 {
mjr 82:4f6209cb5c33 51 if (i > 0) *p++ = ',';
mjr 82:4f6209cb5c33 52 sprintf(p, "%02x", bytes[i]);
mjr 82:4f6209cb5c33 53 p += 2;
mjr 82:4f6209cb5c33 54 }
mjr 82:4f6209cb5c33 55 *p = '\0';
mjr 82:4f6209cb5c33 56 return buf;
mjr 82:4f6209cb5c33 57 }
mjr 82:4f6209cb5c33 58 #else
mjr 82:4f6209cb5c33 59 # define dprintf(...)
mjr 82:4f6209cb5c33 60 #endif
mjr 82:4f6209cb5c33 61
mjr 82:4f6209cb5c33 62 // --------------------------------------------------------------------------
mjr 82:4f6209cb5c33 63 //
mjr 82:4f6209cb5c33 64 // Bit-bang I2C implementation
mjr 82:4f6209cb5c33 65 //
mjr 82:4f6209cb5c33 66 BitBangI2C::BitBangI2C(PinName sda, PinName scl) :
mjr 82:4f6209cb5c33 67 sclPin(scl), sdaPin(sda)
mjr 82:4f6209cb5c33 68 {
mjr 82:4f6209cb5c33 69 // set the default frequency to 100kHz
mjr 82:4f6209cb5c33 70 setFrequency(100000);
mjr 82:4f6209cb5c33 71
mjr 82:4f6209cb5c33 72 // start with pins in high Z state
mjr 82:4f6209cb5c33 73 this->sda(1);
mjr 82:4f6209cb5c33 74 this->scl(1);
mjr 82:4f6209cb5c33 75 }
mjr 82:4f6209cb5c33 76
mjr 82:4f6209cb5c33 77 void BitBangI2C::setFrequency(uint32_t freq)
mjr 82:4f6209cb5c33 78 {
mjr 82:4f6209cb5c33 79 // figure the wait time per half-bit in microseconds for this frequency,
mjr 82:4f6209cb5c33 80 // with a minimum of 1us
mjr 82:4f6209cb5c33 81 clkPeriod_us = 500000/freq;
mjr 82:4f6209cb5c33 82 if (clkPeriod_us < 1)
mjr 82:4f6209cb5c33 83 clkPeriod_us = 1;
mjr 82:4f6209cb5c33 84 }
mjr 82:4f6209cb5c33 85
mjr 82:4f6209cb5c33 86 void BitBangI2C::start()
mjr 82:4f6209cb5c33 87 {
mjr 82:4f6209cb5c33 88 // take clock high
mjr 82:4f6209cb5c33 89 scl(1);
mjr 82:4f6209cb5c33 90 wait_us(clkPeriod_us);
mjr 82:4f6209cb5c33 91
mjr 82:4f6209cb5c33 92 // take data high
mjr 82:4f6209cb5c33 93 sda(1);
mjr 82:4f6209cb5c33 94 wait_us(clkPeriod_us);
mjr 82:4f6209cb5c33 95
mjr 82:4f6209cb5c33 96 // take data low
mjr 82:4f6209cb5c33 97 sda(0);
mjr 82:4f6209cb5c33 98 wait_us(clkPeriod_us);
mjr 82:4f6209cb5c33 99
mjr 82:4f6209cb5c33 100 // take clock low
mjr 82:4f6209cb5c33 101 scl(0);
mjr 82:4f6209cb5c33 102 wait_us(clkPeriod_us);
mjr 82:4f6209cb5c33 103 }
mjr 82:4f6209cb5c33 104
mjr 82:4f6209cb5c33 105 void BitBangI2C::stop()
mjr 82:4f6209cb5c33 106 {
mjr 82:4f6209cb5c33 107 // take SCL high
mjr 82:4f6209cb5c33 108 scl(1);
mjr 82:4f6209cb5c33 109 wait_us(clkPeriod_us);
mjr 82:4f6209cb5c33 110
mjr 82:4f6209cb5c33 111 // take SDA high
mjr 82:4f6209cb5c33 112 sda(1);
mjr 82:4f6209cb5c33 113 wait_us(clkPeriod_us);
mjr 82:4f6209cb5c33 114 }
mjr 82:4f6209cb5c33 115
mjr 82:4f6209cb5c33 116 bool BitBangI2C::wait(uint32_t timeout_us)
mjr 82:4f6209cb5c33 117 {
mjr 82:4f6209cb5c33 118 // set up a timer to monitor the timeout period
mjr 82:4f6209cb5c33 119 Timer t;
mjr 82:4f6209cb5c33 120 t.start();
mjr 82:4f6209cb5c33 121
mjr 82:4f6209cb5c33 122 // wait for an ACK
mjr 82:4f6209cb5c33 123 for (;;)
mjr 82:4f6209cb5c33 124 {
mjr 82:4f6209cb5c33 125 // if SDA is low, it's an ACK
mjr 82:4f6209cb5c33 126 if (!sdaPin.read())
mjr 82:4f6209cb5c33 127 return true;
mjr 82:4f6209cb5c33 128
mjr 82:4f6209cb5c33 129 // if we've reached the timeout, abort
mjr 82:4f6209cb5c33 130 if (t.read_us() > timeout_us)
mjr 82:4f6209cb5c33 131 return false;
mjr 82:4f6209cb5c33 132
mjr 82:4f6209cb5c33 133 // wait briefly
mjr 82:4f6209cb5c33 134 wait_us(20);
mjr 82:4f6209cb5c33 135 }
mjr 82:4f6209cb5c33 136 }
mjr 82:4f6209cb5c33 137
mjr 82:4f6209cb5c33 138 void BitBangI2C::reset()
mjr 82:4f6209cb5c33 139 {
mjr 82:4f6209cb5c33 140 // write out 9 '1' bits
mjr 82:4f6209cb5c33 141 for (int i = 0 ; i < 9 ; ++i)
mjr 82:4f6209cb5c33 142 writeBit(1);
mjr 82:4f6209cb5c33 143
mjr 82:4f6209cb5c33 144 // issue a start sequence
mjr 82:4f6209cb5c33 145 start();
mjr 82:4f6209cb5c33 146
mjr 82:4f6209cb5c33 147 // take the clock high
mjr 82:4f6209cb5c33 148 scl(1);
mjr 82:4f6209cb5c33 149 wait_us(clkPeriod_us);
mjr 82:4f6209cb5c33 150 }
mjr 82:4f6209cb5c33 151
mjr 82:4f6209cb5c33 152 int BitBangI2C::write(uint8_t addr, const uint8_t *data, size_t len, bool repeated)
mjr 82:4f6209cb5c33 153 {
mjr 82:4f6209cb5c33 154 dprintf("i2c.write, addr=%02x [%s] %srepeat\r\n",
mjr 82:4f6209cb5c33 155 addr, dbgbytes(data, len), repeated ? "" : "no ");
mjr 82:4f6209cb5c33 156
mjr 82:4f6209cb5c33 157 // send the start signal
mjr 82:4f6209cb5c33 158 start();
mjr 82:4f6209cb5c33 159
mjr 82:4f6209cb5c33 160 // send the address with the R/W bit set to WRITE (0)
mjr 82:4f6209cb5c33 161 if (write(addr))
mjr 82:4f6209cb5c33 162 {
mjr 82:4f6209cb5c33 163 eprintf(". i2c.write, address write failed, addr=%02x [%s] %srepeat\r\n",
mjr 82:4f6209cb5c33 164 addr, dbgbytes(data, len), repeated ? "": "no ");
mjr 82:4f6209cb5c33 165 return -1;
mjr 82:4f6209cb5c33 166 }
mjr 82:4f6209cb5c33 167
mjr 82:4f6209cb5c33 168 // send the data bytes
mjr 82:4f6209cb5c33 169 for (int i = 0 ; i < len ; ++i)
mjr 82:4f6209cb5c33 170 {
mjr 82:4f6209cb5c33 171 if (write(data[i]))
mjr 82:4f6209cb5c33 172 {
mjr 82:4f6209cb5c33 173 eprintf(". i2c.write, write failed at byte %d, addr=%02x [%s] %srepeat\r\n",
mjr 82:4f6209cb5c33 174 i, addr, dbgbytes(data, len), repeated ? "" : "no ");
mjr 82:4f6209cb5c33 175 return -2;
mjr 82:4f6209cb5c33 176 }
mjr 82:4f6209cb5c33 177 }
mjr 82:4f6209cb5c33 178
mjr 82:4f6209cb5c33 179 // send the stop, unless the start is to be repeated
mjr 82:4f6209cb5c33 180 if (!repeated)
mjr 82:4f6209cb5c33 181 stop();
mjr 82:4f6209cb5c33 182
mjr 82:4f6209cb5c33 183 // success
mjr 82:4f6209cb5c33 184 return 0;
mjr 82:4f6209cb5c33 185 }
mjr 82:4f6209cb5c33 186
mjr 82:4f6209cb5c33 187 int BitBangI2C::read(uint8_t addr, uint8_t *data, size_t len, bool repeated)
mjr 82:4f6209cb5c33 188 {
mjr 82:4f6209cb5c33 189 dprintf("i2c.read, addr=%02x\r\n", addr);
mjr 82:4f6209cb5c33 190
mjr 82:4f6209cb5c33 191 // send the start signal
mjr 82:4f6209cb5c33 192 start();
mjr 82:4f6209cb5c33 193
mjr 82:4f6209cb5c33 194 // send the address with the R/W bit set to READ (1)
mjr 82:4f6209cb5c33 195 if (write(addr | 0x01))
mjr 82:4f6209cb5c33 196 {
mjr 82:4f6209cb5c33 197 eprintf(". i2c.read, read addr write failed, addr=%02x [%s] %srepeat\r\n",
mjr 82:4f6209cb5c33 198 addr, dbgbytes(data, len), repeated ? "" : "no ");
mjr 82:4f6209cb5c33 199 return -1;
mjr 82:4f6209cb5c33 200 }
mjr 82:4f6209cb5c33 201
mjr 82:4f6209cb5c33 202 // Read the data. Send an ACK after each byte except the last,
mjr 82:4f6209cb5c33 203 // where we send a NAK.
mjr 82:4f6209cb5c33 204 for ( ; len != 0 ; --len, ++data)
mjr 82:4f6209cb5c33 205 *data = read(len > 1);
mjr 82:4f6209cb5c33 206
mjr 82:4f6209cb5c33 207 // send the stop signal, unless a repeated start is indicated
mjr 82:4f6209cb5c33 208 if (!repeated)
mjr 82:4f6209cb5c33 209 stop();
mjr 82:4f6209cb5c33 210
mjr 82:4f6209cb5c33 211 // success
mjr 82:4f6209cb5c33 212 return 0;
mjr 82:4f6209cb5c33 213 }
mjr 82:4f6209cb5c33 214
mjr 82:4f6209cb5c33 215 int BitBangI2C::write(uint8_t data)
mjr 82:4f6209cb5c33 216 {
mjr 82:4f6209cb5c33 217 // write the bits, most significant first
mjr 82:4f6209cb5c33 218 for (int i = 0 ; i < 8 ; ++i, data <<= 1)
mjr 82:4f6209cb5c33 219 writeBit(data & 0x80);
mjr 82:4f6209cb5c33 220
mjr 82:4f6209cb5c33 221 // read and return the ACK bit
mjr 82:4f6209cb5c33 222 return readBit();
mjr 82:4f6209cb5c33 223 }
mjr 82:4f6209cb5c33 224
mjr 82:4f6209cb5c33 225 int BitBangI2C::read(bool ack)
mjr 82:4f6209cb5c33 226 {
mjr 82:4f6209cb5c33 227 // read 8 bits, most significant first
mjr 82:4f6209cb5c33 228 uint8_t data = 0;
mjr 82:4f6209cb5c33 229 for (int i = 0 ; i < 8 ; ++i)
mjr 82:4f6209cb5c33 230 data = (data << 1) | readBit();
mjr 82:4f6209cb5c33 231
mjr 82:4f6209cb5c33 232 // switch to output mode and send the ACK bit
mjr 82:4f6209cb5c33 233 writeBit(!ack);
mjr 82:4f6209cb5c33 234
mjr 82:4f6209cb5c33 235 // return the data byte we read
mjr 82:4f6209cb5c33 236 return data;
mjr 82:4f6209cb5c33 237 }
mjr 82:4f6209cb5c33 238
mjr 82:4f6209cb5c33 239 void BitBangI2C::writeBit(int bit)
mjr 82:4f6209cb5c33 240 {
mjr 82:4f6209cb5c33 241 // express the bit on the SDA line
mjr 82:4f6209cb5c33 242 if (bit)
mjr 82:4f6209cb5c33 243 sdaPin.input();
mjr 82:4f6209cb5c33 244 else
mjr 82:4f6209cb5c33 245 {
mjr 82:4f6209cb5c33 246 sdaPin.output();
mjr 82:4f6209cb5c33 247 sdaPin.write(0);
mjr 82:4f6209cb5c33 248 }
mjr 82:4f6209cb5c33 249
mjr 82:4f6209cb5c33 250 // clock it
mjr 82:4f6209cb5c33 251 wait_us(clkPeriod_us);
mjr 82:4f6209cb5c33 252 sclPin.input();
mjr 82:4f6209cb5c33 253
mjr 82:4f6209cb5c33 254 wait_us(clkPeriod_us);
mjr 82:4f6209cb5c33 255 sclPin.output();
mjr 82:4f6209cb5c33 256 sclPin.write(0);
mjr 82:4f6209cb5c33 257
mjr 82:4f6209cb5c33 258 wait_us(clkPeriod_us);
mjr 82:4f6209cb5c33 259 }
mjr 82:4f6209cb5c33 260
mjr 82:4f6209cb5c33 261 int BitBangI2C::readBit()
mjr 82:4f6209cb5c33 262 {
mjr 82:4f6209cb5c33 263 // take the clock high (actually, release it to the pull-up)
mjr 82:4f6209cb5c33 264 scl(1);
mjr 82:4f6209cb5c33 265
mjr 82:4f6209cb5c33 266 // Wait (within reason) for it to actually read as high. The device
mjr 82:4f6209cb5c33 267 // can intentionally pull the clock line low to tell us to wait while
mjr 82:4f6209cb5c33 268 // it's working on preparing the data for us.
mjr 82:4f6209cb5c33 269 Timer t;
mjr 82:4f6209cb5c33 270 t.start();
mjr 82:4f6209cb5c33 271 while (sclPin.read() == 0 && t.read_us() < 500000) ;
mjr 82:4f6209cb5c33 272
mjr 82:4f6209cb5c33 273 // if the clock isn't high, we timed out
mjr 82:4f6209cb5c33 274 if (sclPin.read() == 0)
mjr 82:4f6209cb5c33 275 {
mjr 82:4f6209cb5c33 276 eprintf("i2c.readBit, clock stretching timeout\r\n");
mjr 82:4f6209cb5c33 277 return 0;
mjr 82:4f6209cb5c33 278 }
mjr 82:4f6209cb5c33 279
mjr 82:4f6209cb5c33 280 // wait until the clock interval is up
mjr 82:4f6209cb5c33 281 while (t.read_us() < clkPeriod_us);
mjr 82:4f6209cb5c33 282
mjr 82:4f6209cb5c33 283 // read the bit
mjr 82:4f6209cb5c33 284 bool bit = sdaPin.read();
mjr 82:4f6209cb5c33 285
mjr 82:4f6209cb5c33 286 // take the clock low again
mjr 82:4f6209cb5c33 287 scl(0);
mjr 82:4f6209cb5c33 288 wait_us(clkPeriod_us);
mjr 82:4f6209cb5c33 289
mjr 82:4f6209cb5c33 290 // return the bit
mjr 82:4f6209cb5c33 291 return bit;
mjr 82:4f6209cb5c33 292 }
mjr 82:4f6209cb5c33 293
mjr 82:4f6209cb5c33 294 // --------------------------------------------------------------------------
mjr 82:4f6209cb5c33 295 //
mjr 82:4f6209cb5c33 296 // Low-level line controls.
mjr 82:4f6209cb5c33 297 //
mjr 82:4f6209cb5c33 298 // - To take a line LOW, we pull it to ground by setting the GPIO pin
mjr 82:4f6209cb5c33 299 // direction to OUTPUT and writing a 0.
mjr 82:4f6209cb5c33 300 //
mjr 82:4f6209cb5c33 301 // - To take a line HIGH, we simply put it in high-Z state by setting
mjr 82:4f6209cb5c33 302 // its GPIO pin direction to INPUT.
mjr 82:4f6209cb5c33 303 //
mjr 82:4f6209cb5c33 304 void BitBangI2C::setLevel(DigitalInOut pin, int level)
mjr 82:4f6209cb5c33 305 {
mjr 82:4f6209cb5c33 306 if (level)
mjr 82:4f6209cb5c33 307 {
mjr 82:4f6209cb5c33 308 // set HIGH - release line by setting pin to INPUT mode
mjr 82:4f6209cb5c33 309 pin.input();
mjr 82:4f6209cb5c33 310 }
mjr 82:4f6209cb5c33 311 else
mjr 82:4f6209cb5c33 312 {
mjr 82:4f6209cb5c33 313 // set LOW - pull line low by setting as OUTPUT and writing 0
mjr 82:4f6209cb5c33 314 pin.output();
mjr 82:4f6209cb5c33 315 pin.write(0);
mjr 82:4f6209cb5c33 316 }
mjr 82:4f6209cb5c33 317 }