Now works on Arduino Mega

GSL1680.ino

@@ -1,28 +1,49 @@
+// Original comments:
 // driver for the GSL1680 touch panel
 // Information gleaned from https://github.com/rastersoft/gsl1680.git and various other sources
 // firmware for the specific panel was found here:- http://www.buydisplay.com/default/5-inch-tft-lcd-module-800x480-display-w-controller-i2c-serial-spi
 // As was some test code.
 // This is for that 800X480 display and the 480x272 from buydisplay.com
+// ------
+// Modified by Helge Langehaug with help from https://forum.pjrc.com/threads/26256-Has-anyone-tried-running-the-GSL16880-capacitive-touchscreen-controller-with-Teensy3
 
 /*
 Pin outs
 the FPC on the touch panel is six pins, pin 1 is to the left pin 6 to the right with the display facing up
 
-pin | function  | Arduino Uno
------------------------------
-1   | SCL       | A5
-2   | SDA       | A4
-3   | VDD (3v3) | 3v3
-4   | Wake      | 4
-5   | Int       | 2
-6   | Gnd       | gnd
+pin | function  | Arduino Mega | Arduino Uno
+--------------------------------------------
+1   | SCL       | SCL(21)      | A5
+2   | SDA       | SDA(20)      | A4
+3   | VDD (3v3) | 3v3          | 3v3
+4   | Wake      | 4            | 4
+5   | Int       | 2            | 2
+6   | Gnd       | gnd          | gnd
 */
 #include <Wire.h>
 #include "Arduino.h"
 
-// set this for teensy3
 #define BIGFLASH
 
+#define GET_FAR_ADDRESS(var) \
+({ \
+uint_farptr_t tmp; \
+\
+__asm__ __volatile__( \
+\
+"ldi %A0, lo8(%1)" "\n\t" \
+"ldi %B0, hi8(%1)" "\n\t" \
+"ldi %C0, hh8(%1)" "\n\t" \
+"clr %D0" "\n\t" \
+: \
+"=d" (tmp) \
+: \
+"p" (&(var)) \
+); \
+tmp; \
+})
+
+
 // TODO define for other resolution
 #ifndef BIGFLASH
 #include "gslfw.h" // this is compacted format made by compress_data.c
@@ -190,25 +211,29 @@ void load_fw(void)
 }
 
 #else
-
 void load_fw(void)
-{
+{    
     uint8_t addr;
     uint8_t Wrbuf[4];
-    uint source_line = 0;
-    uint source_len = sizeof(GSLX680_FW) / sizeof(struct fw_data);
-
+    uint16_t source_line = 0;
+    uint16_t source_len = sizeof(GSLX680_FW) / sizeof(struct fw_data);
+    Serial.print("Firmware size: "); Serial.println(sizeof(GSLX680_FW));
+    Serial.print("Line numbers : "); Serial.println(source_len);
 
     for (source_line = 0; source_line < source_len; source_line++) {
-        addr = GSLX680_FW[source_line].offset;
-        Wrbuf[0] = (char)(GSLX680_FW[source_line].val & 0x000000ff);
-        Wrbuf[1] = (char)((GSLX680_FW[source_line].val & 0x0000ff00) >> 8);
-        Wrbuf[2] = (char)((GSLX680_FW[source_line].val & 0x00ff0000) >> 16);
-        Wrbuf[3] = (char)((GSLX680_FW[source_line].val & 0xff000000) >> 24);
+
+       addr = pgm_read_byte_far(GET_FAR_ADDRESS(GSLX680_FW[0].offset)+source_line*5);
+
+       Wrbuf[0] = (char) (pgm_read_dword_far(GET_FAR_ADDRESS(GSLX680_FW[0].val)+source_line*5) & 0x000000ff);
 
-        i2c_write(addr, Wrbuf, 4);
+       Wrbuf[1] = (char) ((pgm_read_dword_far(GET_FAR_ADDRESS(GSLX680_FW[0].val)+source_line*5) & 0x0000ff00) >> 8);
+       Wrbuf[2] = (char) ((pgm_read_dword_far(GET_FAR_ADDRESS(GSLX680_FW[0].val)+source_line*5) & 0x00ff0000) >> 16);
+       Wrbuf[3] = (char) ((pgm_read_dword_far(GET_FAR_ADDRESS(GSLX680_FW[0].val)+source_line*5) & 0xff000000) >> 24);
+
+       i2c_write(addr, Wrbuf, 4);
     }
 }
+
 #endif
 
 void startup_chip(void)
@@ -228,16 +253,22 @@ void init_chip()
 	digitalWrite(WAKE, LOW);
 	delay(50);
 	digitalWrite(WAKE, HIGH);
-	delay(30);
+	delay(10);
 
 	// CTP startup sequence
 	Serial.println("clr reg");
 	clr_reg();
+	delay(50);
+
 	Serial.println("reset_chip");
 	reset_chip();
+	delay(10);
+
 	Serial.println("load_fw");
 	load_fw();
-	//startup_chip();
+	delay(50);
+
+        startup_chip();
 	Serial.println("reset_chip2");
 	reset_chip();
 	Serial.println("startup_chip");
@@ -290,7 +321,7 @@ void setup() {
 	pinMode(WAKE, OUTPUT);
 	digitalWrite(WAKE, LOW);
 	pinMode(INTRPT, INPUT_PULLUP);
-	delay(100);
+	delay(10);
 	Wire.begin();
 	init_chip();
 
@@ -303,14 +334,15 @@ void setup() {
 
 void loop() {
 	if(digitalRead(INTRPT) == HIGH) {
-		digitalWrite(LED, led);
-		led= !led;
+		//digitalWrite(LED, led);
+		//led= !led;
 		int n= read_data();
 		for(int i=0; i<n; i++){
 			Serial.print(ts_event.coords[i].finger); Serial.print(" "), Serial.print(ts_event.coords[i].x); Serial.print(" "), Serial.print(ts_event.coords[i].y);
 		 	Serial.println("");
 		}
 		Serial.println("---");
 	}
+
 }
 

README.md

@@ -1,9 +1,10 @@
 # GSL1680
-Arduino library for the GSL1680 touch panel controller
+Arduino library for the GSL1680 touch panel controller.
 
-Currently just a test sketch, hard coded for the 800x640 5" panel.
+Currently works for Arduino MEGA and hardcoded for 800x640 5" capacitive touch panel from BuyDisplay.
 
-The firmware file is big so it needed to be compressed to fit in an Uno flash memory.
+The firmware file is big so it needed to be compressed to fit in an Uno flash memory (currently not tested)
 
-Once tested and working I'll convert to a library, and have a #define for the two version of firmware
-for the 5" panels from buydisplay.com.
+Fork of wolfmanjm/GSL1680 and updated to work with Arduino Mega, ref. discussions on: https://forum.pjrc.com/threads/26256-Has-anyone-tried-running-the-GSL16880-capacitive-touchscreen-controller-with-Teensy3
+
+Blog entry: https://weatherhelge.wordpress.com/2015/02/09/5-capacitive-touch-panel-with-gsl1680-upn-running-with-arduino/