Revision 0:9f43f6e0d6ad, committed 2017-10-08

Comitter:

davidr99

Date:

Sun Oct 08 00:32:58 2017 +0000

Child:

1:442e873e4f52

Commit message:

First Checkin of PWM LED Matrix

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Sun Oct 08 00:32:58 2017 +0000
@@ -0,0 +1,171 @@
+/*
+The goal of this program is to show the basic connections and workings of Adafruits 32x16 RGB LED matrix board (http://www.adafruit.com/products/420),
+also sold on other places, for instance http://www.ebay.com/itm/PH6-RGB-Full-Color-LED-16-32-Dot-Matrix-Display-Module-/310303408628?pt=LH_DefaultDomain_0&hash=item483f8641f4 (no
+affiliation with either of them).
+This program is not intended to be highly optimized or a guideline in C programming in any way (more of the opposite actually).
+To have more than 7 colors on this thing, you need to implement software PWM of some sort. I have obviously not done that, but if YOU do, please let me know!
+Adafruit have a wicked demo program for an arduino - www.youtube.com/watch?v=lY-flFEfsHo
+There are probably lots of ways to make this perform better, perhaps by using Neal Hormans port of the Adafruit_GFX library (http://mbed.org/users/nkhorman/code/Adafruit_GFX/).
+No error checking or out-of-bounds checking is done. Use at your own peril.
+For more detailed information on the driver chip, see http://www.bjtopspace.com/ziliao/CYT62726.pdf
+Although the chips on my board says jx15020, I've been informed that they are equvivalent to the CYT62726, and so far it's a match.
+Feel free to use all or parts of this work.
+If you choose to do so, I would appreciate a small mentioning in the scrolling opening credits ;)
+
+Best regards,
+Hugo Harming
+upgraded@hotmail.com
+*/
+
+#include "mbed.h"
+#include "rtos.h"
+#define LOW 0
+#define HIGH 1
+
+BusOut ABCD(D5,D6,D7,D8); // Row address.
+DigitalOut CLK(D9);    //  Data clock    - rising edge
+DigitalOut LAT(D3);    //  Data latch    - active low (pulse up after data load)
+DigitalOut OE(D4);     //  Output enable - active low (hold high during data load, bring low after LAT pulse)
+DigitalOut R1(D10);     //  RED   Serial in for upper half
+DigitalOut R2(D13);     //  RED   Serial in for lower half
+DigitalOut G1(D11);      //  GREEN Serial in for upper half
+DigitalOut G2(A0);      //  GREEN Serial in for lower half
+DigitalOut B1(D12);      //  BLUE  Serial in for upper half
+DigitalOut B2(A1);      //  BLUE  Serial in for lower half
+
+const int nPlanes = 5;
+
+unsigned char gm[64][16][nPlanes]; // Buffer with 32x6 bytes. Graphics memory if you like.
+unsigned int plane; //        Counter for demo code
+
+void Init()
+{
+    // Set up things to a known state
+    CLK = LOW;
+    LAT = LOW;
+    OE = HIGH; //display off
+    ABCD = 0;
+    plane=0;
+}
+
+void WrRow(unsigned char Row)
+{
+    // Write specified row (and row+8) to display. Valid input: 0 to 7.
+    ABCD=15-Row; // Set row address
+    for(int col=63; col >= 0; col--) { // To daisychain more displays, I guess you would have to increase this counter to n*32 columns. Might mirror though.
+        char val = gm[col][Row][plane];
+        
+        R1 = (val & 1); // Red bit, upper half
+        G1 = (val & 2); // Green bit, upper half
+        B1 = (val & 4); // Blue bit, upper half
+        
+        R2 = (val & 8); // Red bit, lower half
+        G2 = (val & 16); // Green bit, lower half
+        B2 = (val & 32); // Blue bit, lower half
+        CLK = HIGH;                 // tick (clock bit in)
+        CLK = LOW;                  // tock
+    }
+    LAT = HIGH; // Latch entire row
+    LAT = LOW;
+}
+
+void Pset(unsigned char x,unsigned char y, unsigned long c)
+{
+    int r, g, b;
+    
+    r = (c & 0xFF);            // Extract red bit from color
+    g = (c & 0xFF00) >> 8;         // Extract green bit from color
+    b = (c & 0xFF0000) >> 16;       // Extract blue bit from color
+    
+    for(int p=0;p<nPlanes;p++)
+    {
+        if (y >= 16)
+        {
+            // Keep last 3 bits
+            gm[x][y - 16][p] = (gm[x][y - 16][p] & 0b111000) + ((r >> p) & 1) + (((g << 1) >> p) & 2) + (((b << 2) >> p) & 4);
+        }
+        else
+        {
+            // keep first 3 bits
+            gm[x][y][p] = (gm[x][y][p] & 0b000111) + ((((r >> p) & 1) + (((g << 1) >> p) & 2) + (((b << 2) >> p) & 4)) << 3);
+        }            
+    }
+}
+
+void Paint()
+{
+    if (plane >= (nPlanes - 1))
+    {
+        plane = 0;
+    }
+    else
+    {
+        plane++;
+    }
+        
+    // Write graphics memory to display
+    for(int Row=0; Row<16; Row++) {
+        OE = HIGH; // Disable output
+        WrRow(Row);
+        OE = LOW; // Enable output
+        wait_us(2 * (1 << plane)); // Wasting some time. Use for whatever else. Probably better with a ticker for the display refresh.
+    }
+    OE = HIGH; // Disable output
+}
+
+void PaintThread()
+{
+    Paint();
+}
+
+int main()
+{
+    Init(); // Set things up    
+    Ticker ticker;
+    ticker.attach(PaintThread, 0.003);
+    
+    while(1) {
+    
+        for(int x=0;x<64;x++)
+        {
+            for(int y=0;y<32;y++)
+            {
+                Pset(x, y, 0xFF0101);
+            }   
+            //Paint(); // Display refresh time sets loop duration.
+        }
+        
+        Thread::wait(1000);
+    
+        for(int c=0; c<16; c++) {
+            for(int x=c; x<(63-c); x++) {// Top side
+                Pset(x,c,c);
+                Thread::wait(10);
+                //Paint(); // Display refresh time sets loop duration.
+            }
+            for(int y=c; y<(31-c); y++) {// Right side
+                Pset(63-c,y,c << 8);
+                Thread::wait(10);
+                //Paint();
+            }
+            for(int x=(63-c); x>=c; x--) {// Bottom side
+                Pset(x,(31-c),c << 16);
+                Thread::wait(10);
+                //Paint();
+            }
+            for(int y=(31-c); y>=c; y--) { // Left side
+                Pset(c,y,c << 8);
+                Thread::wait(10);
+                //Paint();
+            }
+        }
+        
+        Thread::wait(1000);
+        
+        /*
+        for(long w=0;w<1000;w++)
+        {
+            Paint(); // Display refresh time sets loop duration.
+        }*/
+    }
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed-rtos.lib	Sun Oct 08 00:32:58 2017 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/mbed_official/code/mbed-rtos/#5713cbbdb706

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed.bld	Sun Oct 08 00:32:58 2017 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/mbed_official/code/mbed/builds/235179ab3f27
\ No newline at end of file