From aac3c16b2987b426f3bdc3ea8f5111a45e66b776 Mon Sep 17 00:00:00 2001
From: Martin Preuss <martin@aquamaniac.de>
Date: Sat, 28 Jan 2023 15:29:58 +0100
Subject: [PATCH] Started working on LCD module.

---
 avr/lcd.asm  | 149 +++++++++++++++++++++++++++++++++++++++++++++++++++
 avr/main.asm |  10 ++--
 2 files changed, 154 insertions(+), 5 deletions(-)
 create mode 100644 avr/lcd.asm

diff --git a/avr/lcd.asm b/avr/lcd.asm
new file mode 100644
index 0000000..3febb52
--- /dev/null
+++ b/avr/lcd.asm
@@ -0,0 +1,149 @@
+
+; ***************************************************************************
+; defines
+
+.equ LCD_CONTROLBYTE_DC_MASK = 0x40
+.equ LCD_CONTROLBYTE_CO_MASK = 0x80
+
+.equ LCD_TWI_ADDRESS         = 0x3c
+
+.equ LCD_WIDTH               = 128
+.equ LCD_HEIGHT              = 64
+
+
+
+; ***************************************************************************
+; data
+
+.dseg
+
+lcdDataBegin:
+lcdDataEnd:
+
+
+
+; ***************************************************************************
+; code
+
+.cseg
+
+
+
+
+LCD_Init:
+ sbi DDRA, PORTA2 ; debug
+ sbi PORTA, PORTA2 ; debug (off)
+
+  ldi zl, LOW(lcdInitCommandsBegin)
+  ldi zh, HIGH(lcdInitCommandsBegin)
+  ldi r16, (lcdInitCommandsEnd-lcdInitCommandsBegin)*2
+  rcall lcdWriteCommandsFromFlash
+
+  ldi r16, 0
+  rcall LCD_Fill
+
+  sec
+  ret
+
+
+
+
+; - R16: number of bytes to send
+; - Z=pointer to data
+lcdWriteCommandsFromFlash:
+  rcall twiStart
+  lsl zl
+  rol zh
+  mov r20, r16   ; number of bytes
+  ldi r16, (LCD_TWI_ADDRESS*2)
+  rcall twiSendByte
+  brcc lcdWriteCommandsFromFlash_error
+  tst r16
+  brne lcdWriteCommandsFromFlash_error
+  
+lcdWriteCommandsFromFlash_loop:
+    lpm r16, z+
+    rcall twiSendByte
+    brcc lcdWriteCommandsFromFlash_error
+    tst r16
+    brne lcdWriteCommandsFromFlash_error
+    dec r20
+  brne lcdWriteCommandsFromFlash_loop
+  rcall twiStop
+ sbi DDRA, PORTA2 ; debug
+ cbi PORTA, PORTA2 ; debug (on)
+  sec
+  ret
+
+lcdWriteCommandsFromFlash_error:
+  rcall twiStop
+  clc
+  ret
+
+
+
+; - R16: data to write
+LCD_Fill:
+  mov r20, r16
+
+  rcall twiStart
+
+  ldi r16, (LCD_TWI_ADDRESS*2)
+  rcall twiSendByte
+  brcc LCD_Fill_error
+  tst r16
+  brne LCD_Fill_error
+
+  ldi r21, 0 ; Y
+LCD_Fill_loopY:
+    ldi r16, 0xb0          ; set page address (data byte and next control byte follow, data byte is a command)
+    add r16, r21
+    rcall twiSendByte
+    brcc LCD_Fill_error
+    tst r16
+    brne LCD_Fill_error
+    ldi r16, 0x01          ; set lower column address
+    rcall twiSendByte
+    brcc LCD_Fill_error
+    tst r16
+    brne LCD_Fill_error
+  
+    ldi r16, 0x10          ; set higher column bits
+    rcall twiSendByte
+    brcc LCD_Fill_error
+    tst r16
+    brne LCD_Fill_error
+  
+    ldi r19, 0
+LCD_Fill_loopX:
+      mov r16, r20
+      rcall twiSendByte
+      brcc LCD_Fill_error
+      tst r16
+      brne LCD_Fill_error
+      inc r19
+      cpi r19, LCD_WIDTH
+    brcs LCD_Fill_loopX
+    
+    inc r21
+    cpi r21, 8
+  brcs LCD_Fill_loopY
+  rcall twiStop
+  sec
+  ret
+LCD_Fill_error:
+  rcall twiStop
+  clc
+  ret
+
+
+
+
+lcdInitCommandsBegin:  ; 28 bytes
+  .db 0xae, 0x00, 0x10, 0x40, 0x81, 0xcf, 0xa1, 0xc8
+  .db 0xa6, 0xa8, 0x3f, 0xd3, 0x00, 0xd5, 0x80, 0xd9
+  .db 0xf1, 0xda, 0x12, 0xdb, 0x40, 0x20, 0x02, 0x8d
+  .db 0x14, 0xa4, 0xa6, 0xaf
+lcdInitCommandsEnd:
+
+
diff --git a/avr/main.asm b/avr/main.asm
index 1979a4d..cb29658 100644
--- a/avr/main.asm
+++ b/avr/main.asm
@@ -91,6 +91,7 @@
 .include "led.asm"
 .include "com.asm"
 .include "twimaster.asm"
+.include "lcd.asm"
 
 
 
@@ -145,8 +146,8 @@ main:
   ldi yh, HIGH(ledA3Sram)
   rcall Led_SetPattern
 
-  ldi r16, 1
-  sts twiMasterScanEnabled, r16
+;  ldi r16, 1
+;  sts twiMasterScanEnabled, r16
 
 main_loop:
     rcall runModulesUntilIdle
@@ -190,6 +191,7 @@ initModules:
   
   rcall Com_Init
   rcall TWI_Master_Init
+  rcall LCD_Init
   ret
 
 
@@ -263,9 +265,7 @@ onEvery100ms:
 ; USED: depending on called routines
 
 onEverySecond:
- sbi DDRA, PORTA2 ; debug
- sbi PINA, PORTA2 ; debug (toggle)
-  rcall TWI_Master_ScanNext
+;  rcall TWI_Master_ScanNext
   ret