hd44780 display debugger

.gitignore

@@ -0,0 +1,2 @@
+*.bin
+

arduino/hd44780_debugger/hd44780_debugger.ino

@@ -0,0 +1,34 @@
+/* HD44780 Character display debugger */
+
+#define EN 2
+#define RS 11
+const byte DATA_BUS[] = {10, 9, 8, 7, 6, 5, 4, 3};
+
+void setup() {
+  pinMode(RS, INPUT);
+  pinMode(EN, INPUT);
+  for(int pin=0; pin < 8; pin++) {
+    pinMode(DATA_BUS[pin], INPUT);
+  }
+
+  Serial.begin(57600);
+  Serial.println("HD44780 debugger");
+  Serial.println("DATA BUS    HEX     RS   EN");
+
+  attachInterrupt(digitalPinToInterrupt(EN), onClk, CHANGE);
+}
+
+void loop() {}
+
+void onClk() {
+  unsigned int data = 0;
+    for(int pin=0; pin < 8; pin++) {
+      byte b = digitalRead(DATA_BUS[pin]) ? 1 : 0;
+      Serial.print(b);
+      data = (data << 1) + b;   // Shifta di 1 e aggiunge il bit corrente. Serve per ricostruire il numero da binario
+    }
+    
+    char output[30] = {};
+    sprintf(output, "    0x%02x    %c    %c", data, digitalRead(RS) ? 'D' : 'I', digitalRead(EN) ? 'H' : 'L');
+    Serial.println(output);
+}

arduino/z80_debugger/z80_debugger.ino

@@ -55,7 +55,8 @@ const byte MODE_ROM_EMULATOR = 1;
 const byte MODE_ROM_RAM_EMULATOR = 2;
 
 const byte ADDR_BUS[] = {50, 52, A11, A9, A8, A12, A15, A14, 53, 51, 49, 47, 45, 43, 41, 39};
-const byte DATA_BUS[] = {34, 40, 42, 44, 46, 36, 30, 32};
+//const byte DATA_BUS[] = {34, 40, 42, 44, 46, 36, 30, 32};
+const byte DATA_BUS[] = {3, 4, 5, 6, 7, 8, 9,10};
 //const byte CTRL_BUS_RD = 20;
 const byte CTRL_BUS_RD = 3;
 const byte CTRL_BUS_WR = 23;
@@ -88,7 +89,7 @@ const byte PWR_VCC = 38;
  *      MODE_ROM_EMULATOR = Emulates rom with the contents of ROM_DATA
  *      MODE_ROM_RAM_EMULATOR = Emulates ram
 */
-const byte MODE = MODE_ROM_EMULATOR;
+const byte MODE = MODE_DEBUGGER;
 
 const byte ROM_DATA[] = {0x00, 0x00, 0x00, 0x00, 0xC3, 0x00, 0x00};
 //const byte ROM_DATA[] = {0x00, 0x00, 0x00, 0x00, 0x76, 0x00, 0x00};

assembly/README.txt

@@ -0,0 +1,7 @@
+Compilare assembly:
+    z80asm -i hd44780_lcd_test_procedure.asm -o rom.bin
+Portare binario alla dimensione dell eeprom:
+    dd if=/dev/zero of=rom.bin bs=1 count=0 seek=8192
+Scrivere su EEPROM:
+    minipro -w rom.bin -p "AT28C64B"
+

assembly/hd44780_lcd_test_procedure.asm

@@ -1,40 +1,39 @@
 ;hd44780 lcd test procedure
 
-ld hl,$4000     ;address reg points to lcd instruction address
+LCD_INSTR_REG: EQU %00000000
+LCD_DATA_REG: EQU %00000001
 
 ;reset procedure
 ld a,%00111000
-ld (hl),a
+out (LCD_INSTR_REG),a
 ld a,%00001000
-ld (hl),a
+out (LCD_INSTR_REG),a
 ld a,%00000001
-ld (hl),a
+out (LCD_INSTR_REG),a
 
 ;init procedure
 ld a,%00111000
-ld (hl),a
+out (LCD_INSTR_REG),a
 ld a,%00001110
-ld (hl),a
+out (LCD_INSTR_REG),a
 
 ;write characters to display
-ld hl,$4001     ;address reg points to lcd data address
-
 ld a,%01000100
-ld (hl),a
+out (LCD_DATA_REG),a
 ld a,%01100001
-ld (hl),a
+out (LCD_DATA_REG),a
 ld a,%01101110
-ld (hl),a
+out (LCD_DATA_REG),a
 ld a,%01101001
-ld (hl),a
+out (LCD_DATA_REG),a
 ld a,%01100101
-ld (hl),a
+out (LCD_DATA_REG),a
 ld a,%01101100
-ld (hl),a
+out (LCD_DATA_REG),a
 ld a,%01100101
-ld (hl),a
+out (LCD_DATA_REG),a
 ld a,%00100001
-ld (hl),a
+out (LCD_DATA_REG),a
 
 halt