From 81669a5442a3d5099de407ad5340e3100f14ca5c Mon Sep 17 00:00:00 2001
From: Martin Preuss <martin@aquamaniac.de>
Date: Mon, 1 Sep 2025 23:24:15 +0200
Subject: [PATCH] avr: first try irq driven com2w interface.

probably doesn't work like that but that's for later.
---
 avr/modules/com2w/com2wi.asm | 579 +++++++++++++++++++++++++++++++++++
 1 file changed, 579 insertions(+)
 create mode 100644 avr/modules/com2w/com2wi.asm

diff --git a/avr/modules/com2w/com2wi.asm b/avr/modules/com2w/com2wi.asm
new file mode 100644
index 0000000..aa66cfc
--- /dev/null
+++ b/avr/modules/com2w/com2wi.asm
@@ -0,0 +1,579 @@
+; ***************************************************************************
+; copyright   : (C) 2025 by Martin Preuss
+; email       : martin@libchipcard.de
+;
+; ***************************************************************************
+; * This file is part of the project "AqHome".                              *
+; * Please see toplevel file COPYING of that project for license details.   *
+; ***************************************************************************
+
+; work in progress!
+
+#ifndef AVR_MODULES_COM2W_COM2WI_H
+#define AVR_MODULES_COM2W_COM2WI_H
+
+
+.equ COM2WI_BUFFER_SIZE = NET_BUFFERS_SIZE-1
+
+.equ COM2WI_R_MAX_WAIT_HI_TIME = 50  ; max 1ms
+.equ COM2WI_S_MAX_WAIT_HI_TIME = 50  ; max 1ms
+.equ COM2WI_S_MAX_WAIT_LO_TIME = 50  ; max 1ms
+
+
+
+.equ COM2WI_STATE_IDLE               = 0
+
+.equ COM2WI_STATE_R_WAITFORCLOCKLO   = 1
+.equ COM2WI_STATE_R_WAITFORCLOCKHI   = 2
+.equ COM2WI_STATE_R_MSGRECVD         = 3
+
+.equ COM2WI_STATE_S_WAITFORCLOCKLO   = 4
+.equ COM2WI_STATE_S_WAITFORCLOCKHI   = 5
+
+.equ COM2WI_STATE_W_WAITFREELINE     = 6
+.equ COM2WI_STATE_W_SENDCLOCKLO      = 7
+.equ COM2WI_STATE_W_SENDCLOCKHI      = 8
+
+.equ COM2WI_STATE_W_WAITBETWEENBITS  = 9
+.equ COM2WI_STATE_W_WAITBETWEENBYTES = 10
+.equ COM2WI_STATE_W_MSGSENT          = 11
+
+.equ COM2WI_STATE_COUNT              = 12
+
+
+
+.equ COM2WI_IFACE_OFFS_BEGIN          = NET_IFACE_SIZE
+.equ   COM2WI_IFACE_OFFS_STATE        = COM2WI_IFACE_OFFS_BEGIN+0
+.equ   COM2WI_IFACE_OFFS_STATETIMER   = COM2WI_IFACE_OFFS_BEGIN+1
+.equ   COM2WI_IFACE_OFFS_STATECOUNTER = COM2WI_IFACE_OFFS_BEGIN+2
+.equ   COM2WI_IFACE_OFFS_PINMASK_CLK  = COM2WI_IFACE_OFFS_BEGIN+3
+.equ   COM2WI_IFACE_OFFS_PINMASK_DATA = COM2WI_IFACE_OFFS_BEGIN+4
+.equ   COM2WI_IFACE_OFFS_BITCOUNTER   = COM2WI_IFACE_OFFS_BEGIN+5
+.equ   COM2WI_IFACE_OFFS_CURRBYTE     = COM2WI_IFACE_OFFS_BEGIN+6
+.equ   COM2WI_IFACE_OFFS_BUFPOS_LOW   = COM2WI_IFACE_OFFS_BEGIN+7
+.equ   COM2WI_IFACE_OFFS_BUFPOS_HIGH  = COM2WI_IFACE_OFFS_BEGIN+8
+.equ   COM2WI_IFACE_OFFS_BUFUSED      = COM2WI_IFACE_OFFS_BEGIN+9
+.equ   COM2WI_IFACE_OFFS_BUFLEFT      = COM2WI_IFACE_OFFS_BEGIN+10
+.equ   COM2WI_IFACE_OFFS_BUFFER       = COM2WI_IFACE_OFFS_BEGIN+11
+.equ COM2WI_IFACE_SIZE                = COM2WI_IFACE_OFFS_BUFFER+COM2WI_BUFFER_SIZE
+
+
+
+
+; ---------------------------------------------------------------------------
+; @macro mCOM2WI_INIT
+;
+; @param @0 interface number (beginning with 0)
+
+.macro mCOM2WI_INIT
+  ldi yl, LOW(com2wi@0_iface)
+  ldi yh, HIGH(com2wi@0_iface)
+  rcall com2wiInit
+  ldi r16, COM_MASK_CLK@0
+  std Y+COM2WI_IFACE_OFFS_PINMASK_CLK, r16
+  ldi r16, COM_MASK_DATA@0
+  std Y+COM2WI_IFACE_OFFS_PINMASK_DATA, r16
+  ldi r16, COM_MASK_IRQ@0
+  std Y+COM2WI_IFACE_OFFS_PINMASK_IRQ, r16
+.endmacro
+; @end
+
+
+
+
+
+.dseg
+
+
+
+com2wi0_iface: .byte COM2WI_IFACE_SIZE
+
+
+
+.cseg
+
+
+
+; ---------------------------------------------------------------------------
+; @routine COM2WI_Init
+
+COM2WI_Init:
+  mCOM2WI_INIT 0
+
+  rcall com2wiSetupTimer1
+  ret
+; @end
+
+
+
+; ---------------------------------------------------------------------------
+; @routine com2wiInit
+
+com2wiInit:
+  rcall com2wiSetupLines
+
+  ldi r16, COM2WI_STATE_IDLE
+  std Y+COM2WI_IFACE_OFFS_STATE, r16
+
+  ret
+; @end
+
+
+
+; ---------------------------------------------------------------------------
+; @routine com2wiSetupLines
+
+com2wiSetupLines:
+  ; setup CLK line (as input, disable internal pull-up resistor)
+.ifdef COM_CLK_PUE
+  ldd r16, Y+COM2WI_IFACE_OFFS_PINMASK_CLK
+  com r16
+  inr r17, COM_CLK_PUE
+  and r17, r16
+  outr COM_CLK_PUE, r17
+.endif
+  rcall com2wiClkSetHigh
+
+  ; setup DATA line (as input, disable internal pull-up resistor)
+.ifdef COM_DATA_PUE
+  ldd r16, Y+COM2WI_IFACE_OFFS_PINMASK_DATA
+  com r16
+  inr r17, COM_DATA_PUE
+  and r17, r16
+  outr COM_DATA_PUE, r17
+.endif
+  rcall com2wiDataSetHigh
+
+  ret
+; @end
+
+
+
+; ---------------------------------------------------------------------------
+; @routine com2wiSetupTimer1
+;
+; setup timer for IRQ every 20us
+
+com2wiSetupTimer1:
+  ; CTC mode, no prescaler, OCR1A=100 (every 20us at 20MHz)
+  ldi r16, 0
+  outr TCCR1A, r16                  ; WGM11=0, WGM10=0
+  ldi r16, (0<<CS12) | (0<<CS11) | (1<<CS10) | (0<<WGM13) | (1<<WGM12)
+  clr r17  HIGH(400)
+  ldi r16, LOW(400)
+  outr OCR1AH, r17
+  outr OCR1AL, r16
+
+  ldi r16, (1<<OCF1A)         ; clear pending interrupts
+  outr TIFR1, r16
+
+  inr r16, TIMSK1
+  sbr r16, (1<<OCIE1A)        ; Timer/Counter1 Output Compare Match A Interrupt Enable
+  outr TIMSK1, r16
+
+  ret
+; @end
+
+
+
+; ---------------------------------------------------------------------------
+; @routine com2wiClkSetHigh
+;
+; @clobbers none
+
+com2wiClkSetHigh:
+  push r16
+    push r17
+      ldd r16, Y+COM2WI_IFACE_OFFS_PINMASK_CLK
+      ; clear bit in io reg (AND with complement)
+      com r16                        
+      inr r17, COM_CLK_DDR
+      and r17, r16
+      outr COM_CLK_DDR, r17          ; make pin input
+.ifndef COM_CLK_PUE
+      inr r17, COM_CLK_OUTPUT
+      and r17, r16                   ; disable pullup
+      outr COM_CLK_OUTPUT, r17
+.endif
+    pop r17
+  pop r16
+  ret
+; @end
+
+
+
+; ---------------------------------------------------------------------------
+; @routine com2wiDataSetHigh
+;
+; @param Y pointer to interface data in SRAM
+; @clobbers none
+
+com2wiDataSetHigh:
+  push r16
+    push r17
+      ldd r16, Y+COM2WI_IFACE_OFFS_PINMASK_DATA
+      ; clear bit in io reg (AND with complement)
+      com r16                        
+      inr r17, COM_DATA_DDR
+      and r17, r16
+      outr COM_DATA_DDR, r17         ; make pin input
+.ifndef COM_DATA_PUE
+      inr r17, COM_DATA_OUTPUT
+      and r17, r16                   ; disable pullup
+      outr COM_DATA_OUTPUT, r17
+.endif
+    pop r17
+  pop r16
+  ret
+; @end
+
+
+
+; ---------------------------------------------------------------------------
+; @routine com2wiDataSetLow
+;
+; @param Y pointer to interface data in SRAM
+; @clobbers none
+
+com2wiDataSetLow:
+  push r16
+    push r17
+      ldd r16, Y+COM2WI_IFACE_OFFS_PINMASK_DATA
+      ; set bit in io reg
+      inr r17, COM_DATA_DDR
+      or r17, r16
+      outr COM_DATA_DDR, r17          ; make pin output
+
+      com r16
+      inr r17, COM_DATA_OUTPUT
+      and r17, r16
+      outr COM_DATA_OUTPUT, r17       ; set pin low
+
+    pop r17
+  pop r16
+  ret
+; @end
+
+
+
+
+com2wiHandleIrq:
+  ldi zl, LOW(com2wiIrqJumpTable)
+  ldi zh, HIGH(com2wiIrqJumpTable)
+  ldd r16, Y+COM2WI_IFACE_OFFS_STATE
+  cpi r16, COM2WI_STATE_COUNT
+  brcc com2wiHandleIrq_ret
+  add zl, r16
+  adc zh, r16
+  sub zh, r16
+  ijmp
+com2wiHandleIrq_ret:
+  ret
+com2wiIrqJumpTable:
+  rjmp com2wiHandleStateIdle         ;  0: COM2WI_STATE_IDLE
+  rjmp com2wiHandleRWaitForClockLo   ;  1: COM2WI_STATE_R_WAITFORCLOCKLO
+  rjmp com2wiHandleRWaitForClockHi   ;  2: COM2WI_STATE_R_WAITFORCLOCKHI
+  rjmp com2wiHandleRMsgRecvd         ;  3: COM2WI_STATE_R_MSGRECVD
+  rjmp com2wiHandleSWaitForClockLo   ;  4: COM2WI_STATE_S_WAITFORCLOCKLO
+  rjmp com2wiHandleSWaitForClockHi   ;  5: COM2WI_STATE_S_WAITFORCLOCKHI
+  rjmp com2wiHandleWWaitFreeLine     ;  6: COM2WI_STATE_W_WAITFREELINE
+  rjmp com2wiHandleWSendClockLo      ;  7: COM2WI_STATE_W_SENDCLOCKLO
+  rjmp com2wiHandleWSendClockHi      ;  8: COM2WI_STATE_W_SENDCLOCKHI
+  rjmp com2wiHandleWWaitBetweenBits  ;  9: COM2WI_STATE_W_WAITBETWEENBITS
+  rjmp com2wiHandleWWaitBetweenBytes ; 10: COM2WI_STATE_W_WAITBETWEENBYTES
+  rjmp com2wiHandleWMsgSent          ; 11: COM2WI_STATE_W_MSGSENT
+
+
+
+com2wiHandleStateIdle:	
+  inr r16, COM_CLK_INPUT
+  ldd r17, Y+COM2WI_IFACE_OFFS_PINMASK_CLK
+  and r16, r17
+  brne com2wiHandleStateIdle_ret
+  ; CLK became low, start reading
+  ldi r16, COM2WI_R_MAX_WAIT_HI_TIME
+  std Y+COM2WI_IFACE_OFFS_STATETIMER, r16
+  ldi r16, COM2WI_STATE_R_WAITFORCLOCKHI
+  std Y+COM2WI_IFACE_OFFS_STATE, r16
+  clr r16
+  std Y+COM2WI_IFACE_OFFS_BITCOUNTER, r16
+com2wiHandleStateIdle_ret:
+  ret
+
+
+; @clobbers r16, r17
+
+com2wiHandleRWaitForClockLo:
+  inr r16, COM_CLK_INPUT
+  ldd r17, Y+COM2WI_IFACE_OFFS_PINMASK_CLK
+  and r16, r17
+  breq com2wiHandleRWaitForClockLo_isLow
+  ; CLK still high, check timer
+  ldd r16, Y+COM2WI_IFACE_OFFS_STATETIMER
+  dec r16
+  std Y+COM2WI_IFACE_OFFS_STATETIMER, r16
+  brne com2wiHandleRWaitForClockLo_ret
+  ; timer ran out, enter idle mode
+  ldi r16, COM2WI_STATE_IDLE
+  std Y+COM2WI_IFACE_OFFS_STATE, r16
+  ret
+com2wiHandleRWaitForClockLo_isLow:
+  ; CLK became low, wait for CLK HI
+  ldi r16, COM2WI_R_MAX_WAIT_HI_TIME
+  std Y+COM2WI_IFACE_OFFS_STATETIMER, r16
+  ldi r16, COM2WI_STATE_R_WAITFORCLOCKHI
+  std Y+COM2WI_IFACE_OFFS_STATE, r16
+com2wiHandleRWaitForClockLo_ret:
+  ret
+
+
+
+; @clobbers r16, r17, r18
+
+com2wiHandleRWaitForClockHi:
+  inr r16, COM_CLK_INPUT
+  ldd r17, Y+COM2WI_IFACE_OFFS_PINMASK_CLK
+  and r16, r17
+  brne com2wiHandleRWaitForClockHi_isHi
+  push xl
+    push xh
+      rcall com2wiHandleRWaitForClockHi_savedRegs
+    pop xh
+  pop xl
+  ret
+com2wiHandleRWaitForClockHi_savedRegs:       ; (r16, r17, r18, X)
+  ; CLK still low, check timer
+  ldd r16, Y+COM2WI_IFACE_OFFS_STATETIMER
+  dec r16
+  std Y+COM2WI_IFACE_OFFS_STATETIMER, r16
+  brne com2wiHandleRWaitForClockHi_ret
+  ; timer ran out, enter skipping mode
+com2wiHandleRWaitForClockHi_enterSkipMode:
+  ldi r16, COM2WI_STATE_S_WAITFORCLOCKHI
+  std Y+COM2WI_IFACE_OFFS_STATE, r16
+  ret
+com2wiHandleRWaitForClockHi_isHi:
+  inr r16, COM_DATA_INPUT
+  ldd r17, Y+COM2WI_IFACE_OFFS_PINMASK_DATA
+  and r16, r17
+  clc
+  breq com2wiHandleRWaitForClockHi_dataInCarry
+  sec
+com2wiHandleRWaitForClockHi_dataInCarry:
+  ldd r16, Y+COM2WI_IFACE_OFFS_CURRBYTE
+  ror r16
+  std Y+COM2WI_IFACE_OFFS_CURRBYTE, r16
+  ldd r16, Y+COM2WI_IFACE_OFFS_BITCOUNTER
+  inc r16
+  std Y+COM2WI_IFACE_OFFS_BITCOUNTER, r16
+  cpi r16, 8
+  brne com2wiHandleRWaitForClockHi_ret
+  ; 8 bits received, store byte
+  ldd xl, Y+COM2WI_IFACE_OFFS_BUFPOS_LOW
+  ldd xh, Y+COM2WI_IFACE_OFFS_BUFPOS_HIGH
+  ldd r17, Y+COM2WI_IFACE_OFFS_BUFLEFT
+  tst r17
+  breq com2wiHandleRWaitForClockHi_overrun
+  dec r17
+  std Y+COM2WI_IFACE_OFFS_BUFLEFT
+  st X+, r16
+  std Y+COM2WI_IFACE_OFFS_BUFPOS_LOW, xl
+  std Y+COM2WI_IFACE_OFFS_BUFPOS_HIGH, xh
+  ldd r18, Y+COM2WI_IFACE_OFFS_BUFUSED
+  inc r18
+  std Y+COM2WI_IFACE_OFFS_BUFUSED, r18
+  tst r17
+  breq com2wiHandleRWaitForClockHi_msgRecvd
+  cpi r18, 2
+  brne com2wiHandleRWaitForClockHi_prepareNextByte
+  ; determine message size
+  inc r16                                         ; last byte was payload length, add byte for crc
+  cp r17, r16                                     ; compare remaining length against remaining space
+  brcs com2wiHandleRWaitForClockHi_badMsgSize
+  std Y+UARTFD_IFACE_OFFS_RBUFLEFT, r16
+  rjmp com2wiHandleRWaitForClockHi_prepareNextByte
+com2wiHandleRWaitForClockHi_msgRecvd:
+  ldi r16, COM2WI_STATE_R_MSGRECVD
+  std Y+COM2WI_IFACE_OFFS_STATE, r16
+#ifdef MODULES_LED_ACTIVITY
+  rcall LedActivity_Trigger                       ; (r16)   [DEBUG]
+#endif
+  ret
+com2wiHandleRWaitForClockHi_overrun:
+  ldi r16, NET_IFACE_OFFS_ERR_CONTENT_LOW
+  rjmp com2wiHandleRWaitForClockHi_error
+com2wiHandleRWaitForClockHi_badMsgSize:
+  ldi r16, NET_IFACE_OFFS_ERR_MSGSIZE_LOW
+com2wiHandleRWaitForClockHi_error:
+  push r24
+    push r25
+      rcall NET_Interface_IncCounter16
+    pop r25
+  pop r24
+  rjmp com2wiHandleRWaitForClockHi_enterSkipMode
+com2wiHandleRWaitForClockHi_prepareNextByte:
+  ; prepare for next byte
+  clr r16
+  std Y+COM2WI_IFACE_OFFS_BITCOUNTER, r16
+  ldi r16, COM2WI_R_MAX_WAIT_LO_TIME
+  std Y+COM2WI_IFACE_OFFS_STATETIMER, r16
+  ldi r16, COM2WI_STATE_R_WAITFORCLOCKLO
+  std Y+COM2WI_IFACE_OFFS_STATE, r16
+com2wiHandleRWaitForClockHi_ret:
+  ret
+
+
+
+; @clobbers r16, r17, r18
+
+com2wiHandleRMsgRecvd:
+  push r19
+    push r20
+      push xl
+        push xh
+          push zl
+            push zh
+              rcall com2wiHandleRMsgRecvd_savedRegs
+            pop zh
+          pop zl
+        pop xh
+      pop xl
+    pop r20
+  pop r19
+  ret
+com2wiHandleRMsgRecvd_savedRegs:          ; (r16, r17, r18, r19, r20, X, Z)
+  ; check message
+  mov xl, yl
+  mov xh, yh
+  adiw xh:xl, UARTFD_IFACE_OFFS_RBUFFER
+  rcall NETMSG_CheckMessageInBuffer       ; (R16, R17, R18, R19, R20, X)
+  brcc com2wiHandleRMsgRecvd_errorCrc
+  ; allocate buffer for storage
+  rcall NET_Buffer_Alloc                  ; R16=number, X=ptr (R16, R17, X)
+  brcc com2wiHandleRMsgRecvd_errorMem
+  ldd r18, Y+NET_IFACE_OFFS_IFACENUM
+  andi r18, 0x0f
+  ld r17, X
+  andi r17, 0xf0
+  or r17, r18
+  st X+, r17                              ; store interface number
+  ; copy to newly allocated buffer
+  mov zl, yl
+  mov zh, yh
+  adiw zh:zl, UARTFD_IFACE_OFFS_RBUFFER
+  ldd r17, Y+UARTFD_IFACE_OFFS_RBUFUSED
+com2wiHandleRMsgRecvd_copyLoop:
+    ld r18, Z+
+    st X+, r18
+    dec r17
+  brne com2wiHandleRMsgRecvd_copyLoop
+  ; add new buffer to incoming list
+
+; DEBUG
+;  rcall NET_AddIncomingMsgNum
+;  brcs com2wiHandleRMsgRecvd_msgSaved
+
+  rcall NET_Buffer_ReleaseByNum           ; (R16, X)
+  rjmp com2wiHandleRMsgRecvd_errorMem
+com2wiHandleRMsgRecvd_msgSaved:
+#ifdef MODULES_LED_ACTIVITY
+  rcall LedActivity_Trigger               ; (r16)
+#endif
+  ldi r16, NET_IFACE_OFFS_PACKETSIN_LOW
+  rcall NET_Interface_IncCounter16        ; (R24, R25)
+  ldi r16, COM2WI_STATE_IDLE
+  std Y+COM2WI_IFACE_OFFS_STATE, r16
+  ret
+com2wiHandleRMsgRecvd_errorCrc:
+  ldi r16, NET_IFACE_OFFS_ERR_CONTENT_LOW
+  rjmp com2wiHandleRMsgRecvd_incCounter
+com2wiHandleRMsgRecvd_errorMem:
+  ldi r16, NET_IFACE_OFFS_ERR_NOBUF_LOW
+com2wiHandleRMsgRecvd_incCounter:
+  rcall NET_Interface_IncCounter16        ; (R24, R25)
+  ldi r16, COM2WI_S_MAX_WAIT_HI_TIME
+  std Y+COM2WI_IFACE_OFFS_STATETIMER, r16
+  ldi r16, COM2WI_STATE_S_WAITFORCLOCKHI
+  std Y+COM2WI_IFACE_OFFS_STATE, r16
+  ret
+; @end
+
+
+
+; @clobbers r16, r17
+
+com2wiHandleSWaitForClockLo:
+  inr r16, COM_CLK_INPUT
+  ldd r17, Y+COM2WI_IFACE_OFFS_PINMASK_CLK
+  and r16, r17
+  breq com2wiHandleSWaitForClockLo_isLow
+  ; is still high, check timer
+  ldd r16, Y+COM2WI_IFACE_OFFS_STATETIMER
+  dec r16
+  std Y+COM2WI_IFACE_OFFS_STATETIMER, r16
+  brne com2wiHandleSWaitForClockLo_ret
+  ; timer ran out, enter idle mode
+  ldi r16, COM2WI_STATE_IDLE
+  std Y+COM2WI_IFACE_OFFS_STATE, r16
+  ret
+com2wiHandleSWaitForClockLo_isLow:
+  ; CLK became low, wait for HIGH again
+  ldi r16, COM2WI_STATE_S_WAITFORCLOCKHI
+  std Y+COM2WI_IFACE_OFFS_STATE, r16
+com2wiHandleSWaitForClockLo_ret:
+  ret
+
+
+
+com2wiHandleSWaitForClockHi:
+  inr r16, COM_CLK_INPUT
+  ldd r17, Y+COM2WI_IFACE_OFFS_PINMASK_CLK
+  and r16, r17
+  breq com2wiHandleSWaitForClockHi_ret
+  ; enter COM2WI_STATE_S_WAITFORCLOCKLO
+  ldi r16, COM2WI_STATE_S_WAITFORCLOCKLO
+  std Y+COM2WI_IFACE_OFFS_STATE, r16
+  ldi r16, COM2WI_S_MAX_WAIT_LO_TIME
+  std Y+COM2WI_IFACE_OFFS_STATETIMER
+com2wiHandleSWaitForClockHi_ret:
+  ret
+
+
+
+
+com2wiHandleWWaitFreeLine:
+  ret
+
+
+
+com2wiHandleWSendClockLo:
+  ret
+
+
+
+com2wiHandleWSendClockHi:
+  ret
+
+
+
+com2wiHandleWWaitBetweenBits:
+  ret
+
+
+
+com2wiHandleWWaitBetweenBytes:
+  ret
+
+
+
+com2wiHandleWMsgSent:
+  ret
+
+
+
+
+
+
+
+#endif
+