An input/output controller for virtual pinball machines, with plunger position tracking, accelerometer-based nudge sensing, button input encoding, and feedback device control.

Dependencies:   USBDevice mbed FastAnalogIn FastIO FastPWM SimpleDMA

/media/uploads/mjr/pinscape_no_background_small_L7Miwr6.jpg

The Pinscape Controller is a special-purpose software project that I wrote for my virtual pinball machine.

New version: V2 is now available! The information below is for version 1, which will continue to be available for people who prefer the original setup.

What exactly is a virtual pinball machine? It's basically a video-game pinball emulator built to look like a real pinball machine. (The picture at right is the one I built.) You start with a standard pinball cabinet, either built from scratch or salvaged from a real machine. Inside, you install a PC motherboard to run the software, and install TVs in place of the playfield and backglass. Several Windows pinball programs can take advantage of this setup, including the open-source project Visual Pinball, which has hundreds of tables available. Building one of these makes a great DIY project, and it's a good way to add to your skills at woodworking, computers, and electronics. Check out the Cabinet Builders' Forum on vpforums.org for lots of examples and advice.

This controller project is a key piece in my setup that helps integrate the video game into the pinball cabinet. It handles several input/output tasks that are unique to virtual pinball machines. First, it lets you connect a mechanical plunger to the software, so you can launch the ball like on a real machine. Second, it sends "nudge" data to the software, based on readings from an accelerometer. This lets you interact with the game physically, which makes the playing experience more realistic and immersive. Third, the software can handle button input (for wiring flipper buttons and other cabinet buttons), and fourth, it can control output devices (for tactile feedback, button lights, flashers, and other special effects).

Documentation

The Hardware Build Guide (PDF) has detailed instructions on how to set up a Pinscape Controller for your own virtual pinball cabinet.

Update notes

December 2015 version: This version fully supports the new Expansion Board project, but it'll also run without it. The default configuration settings haven't changed, so existing setups should continue to work as before.

August 2015 version: Be sure to get the latest version of the Config Tool for windows if you're upgrading from an older version of the firmware. This update adds support for TSL1412R sensors (a version of the 1410 sensor with a slightly larger pixel array), and a config option to set the mounting orientation of the board in the firmware rather than in VP (for better support for FP and other pinball programs that don't have VP's flexibility for setting the rotation).

Feb/March 2015 software versions: If you have a CCD plunger that you've been using with the older versions, and the plunger stops working (or doesn't work as well) after you update to the latest version, you might need to increase the brightness of your light source slightly. Check the CCD exposure with the Windows config tool to see if it looks too dark. The new software reads the CCD much more quickly than the old versions did. This makes the "shutter speed" faster, which might require a little more light to get the same readings. The CCD is actually really tolerant of varying light levels, so you probably won't have to change anything for the update - I didn't. But if you do have any trouble, have a look at the exposure meter and try a slightly brighter light source if the exposure looks too dark.

Downloads

  • Config tool for Windows (.exe and C# source): this is a Windows program that lets you view the raw pixel data from the CCD sensor, trigger plunger calibration mode, and configure some of the software options on the controller.
  • 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 9.9.1 and VP 10 releases, so you don't need my custom builds if you're using 9.9.1 or 10 or later. I don't think there's any reason to use my 9.9 instead of the official 9.9.1, but I'm leaving it here just in case. In the official VP releases, look for the checkbox "Enable Nudge Filter" in the Keys preferences dialog. (There's no checkbox in my custom builds, though; the filter is simply always on in those.)
  • Output circuit shopping list: This is a saved shopping cart at mouser.com with the parts needed for each output driver, if you want to use the LedWiz emulator feature. Note that quantities in the cart are for one output channel, so multiply everything by the number of channels you plan to use, except that you only need one of the ULN2803 transistor array chips for each eight output circuits.
  • 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.

Features

  • Plunger position sensing, using a TAOS TSL 1410R CCD linear array sensor. This sensor is a 1280 x 1 pixel array at 400 dpi, which makes it about 3" long - almost exactly the travel distance of a standard pinball plunger. The idea is that you install the sensor just above (within a few mm of) the shooter rod on the inside of the cabinet, with the CCD window facing down, aligned with and centered on the long axis of the shooter rod, and positioned so that the rest position of the tip is about 1/2" from one end of the window. As you pull back the plunger, the tip will travel down the length of the window, and the maximum retraction point will put the tip just about at the far end of the window. Put a light source below, facing the sensor - I'm using two typical 20 mA blue LEDs about 8" away (near the floor of the cabinet) with good results. The principle of operation is that the shooter rod casts a shadow on the CCD, so pixels behind the rod will register lower brightness than pixels that aren't in the shadow. We scan down the length of the sensor for the edge between darker and brighter, and this tells us how far back the rod has been pulled. We can read the CCD at about 25-30 ms intervals, so we can get rapid updates. We pass the readings reports to VP via our USB joystick reports.

    The hardware build guide includes schematics showing how to wire the CCD to the KL25Z. It's pretty straightforward - five wires between the two devices, no external components needed. Two GPIO ports are used as outputs to send signals to the device and one is used as an ADC in to read the pixel brightness inputs. The config tool has a feature that lets you display the raw pixel readings across the array, so you can test that the CCD is working and adjust the light source to get the right exposure level.

    Alternatively, you can use a slide potentiometer as the plunger sensor. This is a cheaper and somewhat simpler option that seems to work quite nicely, as you can see in Lemming77's video of this setup in action. This option is also explained more fully in the build guide.
  • Nudge sensing via the KL25Z's on-board accelerometer. Mounting the board in your cabinet makes it feel the same accelerations the cabinet experiences when you nudge it. Visual Pinball already knows how to interpret accelerometer input as nudging, so we simply feed the acceleration readings to VP via the joystick interface.
  • Cabinet button wiring. Up to 24 pushbuttons and switches can be wired to the controller for input controls (for example, flipper buttons, the Start button, the tilt bob, coin slot switches, and service door buttons). These appear to Windows as joystick buttons. VP can map joystick buttons to pinball inputs via its keyboard preferences dialog. (You can raise the 24-button limit by editing the source code, but since all of the GPIO pins are allocated, you'll have to reassign pins currently used for other functions.)
  • LedWiz emulation (limited). In addition to emulating a joystick, the device emulates the LedWiz USB interface, so controllers on the PC side such as DirectOutput Framework can recognize it and send it commands to control lights, solenoids, and other feedback devices. 22 GPIO ports are assigned by default as feedback device outputs. This feature has some limitations. The big one is that the KL25Z hardware only has 10 PWM channels, which isn't enough for a fully decked-out cabinet. You also need to build some external power driver circuitry to use this feature, because of the paltry 4mA output capacity of the KL25Z GPIO ports. The build guide includes instructions for a simple and robust output circuit, including part numbers for the exact components you need. It's not hard if you know your way around a soldering iron, but just be aware that it'll take a little work.

Warning: This is not replacement software for the VirtuaPin plunger kit. If you bought the VirtuaPin kit, please don't try to install this software. The VP kit happens to use the same microcontroller board, but the rest of its hardware is incompatible. The VP kit uses a different type of sensor for its plunger and has completely different button wiring, so the Pinscape software won't work properly with it.

Revision:
21:5048e16cc9ef
Parent:
20:4c43877327ab
Child:
22:71422c359f2a
--- a/main.cpp	Sat Feb 28 00:32:57 2015 +0000
+++ b/main.cpp	Sat Mar 28 07:59:47 2015 +0000
@@ -216,6 +216,7 @@
 #include "crc32.h"
 
 // our local configuration file
+#define DECL_EXTERNS
 #include "config.h"
 
 
@@ -260,15 +261,20 @@
 
 // --------------------------------------------------------------------------
 //
-// Potentiometer configuration
+// Define a symbol to tell us whether any sort of plunger sensor code
+// is enabled in this build.  Note that this doesn't tell us that a
+// plunger device is actually attached or *currently* enabled; it just
+// tells us whether or not the code for plunger sensing is enabled in 
+// the software build.  This lets us leave out some unnecessary code
+// on installations where no physical plunger is attached.
 //
-#ifdef POT_SENSOR_ENABLED
-#define IF_POT(x) x
+const int PLUNGER_CODE_ENABLED =
+#if defined(ENABLE_CCD_SENSOR) || defined(ENABLE_POT_SENSOR)
+    1;
 #else
-#define IF_POT(x)
+    0;
 #endif
 
-
 // ---------------------------------------------------------------------------
 //
 // On-board RGB LED elements - we use these for diagnostic displays.
@@ -1049,8 +1055,8 @@
         cfg.d.plungerMin = 0;        // assume we can go all the way forward...
         cfg.d.plungerMax = npix;     // ...and all the way back
         cfg.d.plungerZero = npix/6;  // the rest position is usually around 1/2" back
-        cfg.d.ledWizUnitNo = DEFAULT_LEDWIZ_UNIT_NUMBER;
-        cfg.d.plungerEnabled = true;
+        cfg.d.ledWizUnitNo = DEFAULT_LEDWIZ_UNIT_NUMBER - 1;  // unit numbering starts from 0 internally
+        cfg.d.plungerEnabled = PLUNGER_CODE_ENABLED;
     }
     
     // Create the joystick USB client.  Note that we use the LedWiz unit
@@ -1094,10 +1100,15 @@
     // create the accelerometer object
     Accel accel(MMA8451_SCL_PIN, MMA8451_SDA_PIN, MMA8451_I2C_ADDRESS, MMA8451_INT_PIN);
     
+#ifdef ENABLE_JOYSTICK
     // last accelerometer report, in joystick units (we report the nudge
     // acceleration via the joystick x & y axes, per the VP convention)
     int x = 0, y = 0;
     
+    // flag: send a pixel dump after the next read
+    bool reportPix = false;
+#endif
+
     // create our plunger sensor object
     PlungerSensor plungerSensor;
 
@@ -1129,9 +1140,10 @@
     //   0 = default
     //   1 = cocked (plunger has been pulled back about 1" from state 0)
     //   2 = uncocked (plunger is pulled back less than 1" from state 1)
-    //   3 = launching (plunger has been released from state 1 or 2, or 
-    //       pushed forward about 1/4" from state 0)
-    //   4 = launching, plunger is no longer pushed forward
+    //   3 = launching, plunger is forward beyond park position
+    //   4 = launching, plunger is behind park position
+    //   5 = pressed and holding (plunger has been pressed forward beyond 
+    //       the park position from state 0)
     int lbState = 0;
     
     // Time since last lbState transition.  Some of the states are time-
@@ -1202,9 +1214,6 @@
     //    0x01  -> plunger sensor enabled
     uint16_t statusFlags = (cfg.d.plungerEnabled ? 0x01 : 0x00);
     
-    // flag: send a pixel dump after the next read
-    bool reportPix = false;
-
     // we're all set up - now just loop, processing sensor reports and 
     // host requests
     for (;;)
@@ -1257,7 +1266,7 @@
                         // 1 = Set Configuration:
                         //     data[2] = LedWiz unit number (0x00 to 0x0f)
                         //     data[3] = feature enable bit mask:
-                        //               0x01 = enable CCD
+                        //               0x01 = enable plunger sensor
                         
                         // we'll need a reset if the LedWiz unit number is changing
                         uint8_t newUnitNo = data[2] & 0x0f;
@@ -1277,6 +1286,7 @@
                         // save the configuration
                         cfg.save(iap, flash_addr);
                     }
+#ifdef ENABLE_JOYSTICK
                     else if (data[1] == 2)
                     {
                         // 2 = Calibrate plunger
@@ -1298,6 +1308,7 @@
                         ledB = 0;
                         ledG = 1;
                     }
+#endif // ENABLE_JOYSTICK
                 }
                 else 
                 {
@@ -1535,11 +1546,11 @@
                 case 0:
                     // Base state.  If the plunger is pulled back by an inch
                     // or more, go to "cocked" state.  If the plunger is pushed
-                    // forward by 1/4" or more, go to "launch" state.
+                    // forward by 1/4" or more, go to "pressed" state.
                     if (znew >= cockThreshold)
                         newState = 1;
                     else if (znew <= pushThreshold)
-                        newState = 3;
+                        newState = 5;
                     break;
                     
                 case 1:
@@ -1585,22 +1596,34 @@
                     else if (lbTimer.read_ms() > 200)
                         newState = 0;                    
                     break;
+                    
+                case 5:
+                    // Press-and-Hold state.  If the plunger is no longer pushed
+                    // forward, AND it's been at least 50ms since we generated
+                    // the simulated Launch Ball button press, return to the base 
+                    // state.  The minimum time is to ensure that VP has a chance
+                    // to see the button press and to avoid transient key bounce
+                    // effects when the plunger position is right on the threshold.
+                    if (znew > pushThreshold && lbTimer.read_ms() > 50)
+                        newState = 0;
+                    break;
                 }
                 
                 // change states if desired
                 const uint32_t lbButtonBit = (1 << (LaunchBallButton - 1));
                 if (newState != lbState)
                 {
-                    // if we're entering Launch state, and the ZB Launch Ball
-                    // LedWiz signal is turned on, simulate a Launch Ball button
-                    // press
-                    if (newState == 3 && lbState != 4 && wizOn[ZBLaunchBallPort-1])
+                    // If we're entering Launch state OR we're entering the
+                    // Press-and-Hold state, AND the ZB Launch Ball LedWiz signal 
+                    // is turned on, simulate a Launch Ball button press.
+                    if (((newState == 3 && lbState != 4) || newState == 5)
+                        && wizOn[ZBLaunchBallPort-1])
                     {
                         lbBtnTimer.reset();
                         lbBtnTimer.start();
                         simButtons |= lbButtonBit;
                     }
-                        
+                    
                     // if we're switching to state 0, release the button
                     if (newState == 0)
                         simButtons &= ~(1 << (LaunchBallButton - 1));
@@ -1611,17 +1634,48 @@
                     // start timing in the new state
                     lbTimer.reset();
                 }
-
-                // if the simulated Launch Ball button press is in effect,
-                // and either it's been in effect too long or the ZB Launch
-                // Ball signal is no longer active, turn off the button
-                if ((simButtons & lbButtonBit) != 0
-                    && (!wizOn[ZBLaunchBallPort-1] || lbBtnTimer.read_ms() > 250))
+                
+                // If the Launch Ball button press is in effect, but the
+                // ZB Launch Ball LedWiz signal is no longer turned on, turn
+                // off the button.
+                //
+                // If we're in one of the Launch states (state #3 or #4),
+                // and the button has been on for long enough, turn it off.
+                // The Launch mode is triggered by a pull-and-release gesture.
+                // From the user's perspective, this is just a single gesture
+                // that should trigger just one momentary press on the Launch
+                // Ball button.  Physically, though, the plunger usually
+                // bounces back and forth for 500ms or so before coming to
+                // rest after this gesture.  That's what the whole state
+                // #3-#4 business is all about - we stay in this pair of
+                // states until the plunger comes to rest.  As long as we're
+                // in these states, we won't send duplicate button presses.
+                // But we also don't want the one button press to continue 
+                // the whole time, so we'll time it out now.
+                //
+                // (This could be written as one big 'if' condition, but
+                // I'm breaking it out verbosely like this to make it easier
+                // for human readers such as myself to comprehend the logic.)
+                if ((simButtons & lbButtonBit) != 0)
                 {
-                    lbBtnTimer.stop();
-                    simButtons &= ~lbButtonBit;
+                    int turnOff = false;
+                    
+                    // turn it off if the ZB Launch Ball signal is off
+                    if (!wizOn[ZBLaunchBallPort-1])
+                        turnOff = true;
+                        
+                    // also turn it off if we're in state 3 or 4 ("Launch"),
+                    // and the button has been on long enough
+                    if ((lbState == 3 || lbState == 4) && lbBtnTimer.read_ms() > 250)
+                        turnOff = true;
+                        
+                    // if we decided to turn off the button, do so
+                    if (turnOff)
+                    {
+                        lbBtnTimer.stop();
+                        simButtons &= ~lbButtonBit;
+                    }
                 }
-
             }
                 
             // If a firing event is in progress, generate synthetic reports to 
@@ -1710,6 +1764,7 @@
         // update the buttons
         uint32_t buttons = readButtons();
 
+#ifdef ENABLE_JOYSTICK
         // If it's been long enough since our last USB status report,
         // send the new report.  We throttle the report rate because
         // it can overwhelm the PC side if we report too frequently.
@@ -1732,6 +1787,13 @@
             x = xa;
             y = ya;
             
+            // Report the current plunger position UNLESS the ZB Launch Ball 
+            // signal is on, in which case just report a constant 0 value.  
+            // ZB Launch Ball turns off the plunger position because it
+            // tells us that the table has a Launch Ball button instead of
+            // a traditional plunger.
+            int zrep = (ZBLaunchBallPort != 0 && wizOn[ZBLaunchBallPort-1] ? 0 : z);
+            
             // Send the status report.  Note that the nominal x and y axes
             // are reversed - this makes it more intuitive to set up in VP.
             // If we mount the Freesale card flat on the floor of the cabinet
@@ -1739,12 +1801,12 @@
             // arrangement of our nominal axes aligns with VP's standard
             // setting, so that we can configure VP with X Axis = X on the
             // joystick and Y Axis = Y on the joystick.
-            js.update(y, x, z, buttons | simButtons, statusFlags);
+            js.update(y, x, zrep, buttons | simButtons, statusFlags);
             
             // we've just started a new report interval, so reset the timer
             reportTimer.reset();
         }
-        
+
         // If we're in pixel dump mode, report all pixel exposure values
         if (reportPix)
         {
@@ -1755,6 +1817,17 @@
             reportPix = false;
         }
         
+#else // ENABLE_JOYSTICK
+        // We're a secondary controller, with no joystick reporting.  Send
+        // a generic status report to the host periodically for the sake of
+        // the Windows config tool.
+        if (reportTimer.read_ms() > 200)
+        {
+            js.updateStatus(0);
+        }
+
+#endif // ENABLE_JOYSTICK
+        
 #ifdef DEBUG_PRINTF
         if (x != 0 || y != 0)
             printf("%d,%d\r\n", x, y);