sending works again with n20.

avr/modules/uart_bitbang2/bytelevel.asm

@@ -104,33 +104,28 @@ uartBitbang_SendByte_loop:                         ; 11 for low bit
 uartBitbang_SendByte_setLow:
     sbi COM_DATA_DDR, COM_DATA_PIN                 ; +2 set DATA as output
     cbi COM_DATA_OUTPUT, COM_DATA_PIN              ; +2 set DATA low
-    Utils_WaitNanoSecs COM_BIT_LENGTH, 11, r22
+    rjmp uartBitbang_SendByte_wait                 ; +2
-    rjmp uartBitbang_SendByte_loopEnd              ; +2
 uartBitbang_SendByte_setHigh:
     cbi COM_DATA_DDR, COM_DATA_PIN                 ; +2 set DATA as input, pullup R makes it ONE
-    nop                                            ; +1 (to make pin change available)
+    cbi COM_DATA_OUTPUT, COM_DATA_PIN              ; +2 disable internal pullup for DATA
-    Utils_WaitNanoSecs COM_HALFBIT_LENGTH, 0, r22  ; wait for half a bit length for line to safely settle
+    nop                                            ; +1
-    sbis COM_DATA_INPUT, COM_DATA_PIN              ; +1 if no skip, +2 if skipped
+    nop                                            ; +1
-      rjmp uartBitbang_SendByte_error              ; +2 if error (collision: we wanted line to be high but it is low)
+uartBitbang_SendByte_wait:
-    Utils_WaitNanoSecs COM_HALFBIT_LENGTH, 11, r22
+    Utils_WaitNanoSecs COM_BIT_LENGTH, 12, r22
-    cbi COM_DATA_DDR, COM_DATA_PIN                 ; +2 set DATA as input, pullup R makes it ONE
-    Utils_WaitNanoSecs COM_BIT_LENGTH, 8, r22
 uartBitbang_SendByte_loopEnd:
     dec r21                                        ; +1
   brne uartBitbang_SendByte_loop                   ; +2, sum per loop: 11 cycles
   ; send stopbit
   cbi COM_DATA_DDR, COM_DATA_PIN                   ; +2 set DATA as input, pullup R makes it ONE
-  Utils_WaitNanoSecs COM_BIT_LENGTH, 0, r22        ; wait for one bit length
+  cbi COM_DATA_OUTPUT, COM_DATA_PIN                ; +2 disable internal pullup for DATA
+  Utils_WaitNanoSecs COM_BIT_LENGTH, 1, r22        ; wait for one bit length
   sec
   ret
-
-uartBitbang_SendByte_error:
-  clc
-  ret
 ; @end
 
 
 
+
 ; ---------------------------------------------------------------------------
 ; @routine uartBitbangReceiveByte
 ;
@@ -204,50 +199,6 @@ uartBitbang_WaitForDataHigh:
 
 
 
-; ---------------------------------------------------------------------------
-; @routine uartBitbang_WaitForAttnHigh
-;
-; Wait up to 1ms for data pin to become high
-; @return CFLAG set if okay, clear otherwise
-; @clobbers R17, R22
-
-uartBitbang_WaitForAttnHigh:
-  cbi COM_ATTN_DDR, COM_ATTN_PIN          ; set ATTN port as input
-  cbi COM_ATTN_OUTPUT, COM_ATTN_PIN       ; disable internal pullup for ATTN
-  UART_BB_M_WAIT_FOR_PIN_HIGH COM_ATTN_INPUT, COM_ATTN_PIN
-  ret
-; @end
-
-
-
-
-; ---------------------------------------------------------------------------
-; @routine uartBitbang_AcquireBus
-;
-; Reserve bus if free (otherwise return error)
-; Expects interrupts to be disabled.
-;
-; @return CFLAG set if okay (bus acquired), cleared on error
-; @clobbers: none
-
-uartBitbang_AcquireBus:
-  ; check for ATTN line: busy?
-  cbi COM_ATTN_DDR, COM_ATTN_PIN                 ; set ATTN as input
-  cbi COM_ATTN_OUTPUT, COM_ATTN_PIN              ; disable pullup on ATTN
-  nop                                            ; needed to sample current input
-  sbis COM_ATTN_INPUT, COM_ATTN_PIN              ; ATTN low?
-    rjmp uartBitbang_AcquireBus_busy             ; jump if it is
-  sbi COM_ATTN_DDR, COM_ATTN_PIN                 ; set ATTN as output
-  cbi COM_ATTN_OUTPUT, COM_ATTN_PIN              ; set ATTN low
-  sec
-  ret
-uartBitbang_AcquireBus_busy:
-  clc
-  ret
-; @end
-
-
-
 ; ---------------------------------------------------------------------------
 ; @routine uartBitbang_WaitForOneBitLength
 ;

avr/modules/uart_bitbang2/iface.asm

@@ -49,6 +49,12 @@ UART_BitBang_Init:
   rcall NET_Interface_Init                ; (R16, R17, X)
 
   ; init hw
+  cbi COM_DATA_DDR, COM_DATA_PIN          ; set TXD port as input
+  cbi COM_DATA_OUTPUT, COM_DATA_PIN       ; disable internal pullup for DATA
+  cbi COM_ATTN_DDR, COM_ATTN_PIN          ; set ATTN port as input
+  cbi COM_ATTN_OUTPUT, COM_ATTN_PIN       ; disable internal pullup for ATTN
+
+  ; enable IRQ
   sbi COM_IRQ_ADDR_ATTN, COM_IRQ_BIT_ATTN ; enable pin change irq for ATTN line
   in r16, GIMSK                           ; enable pin change irq PCIE0 or PCIE1
   ori r16, (1<<COM_IRQ_GIMSK_ATTN)
@@ -123,16 +129,12 @@ uartBitBang_sendNextPkg:
   rcall NET_Buffer_Locate                    ; get pointer to buffer (R17)
   brcc uartBitBang_sendNextPkg_end
   adiw xh:xl, 1                              ; skip buffer header
-  rcall uartBitbang_SendMsg                  ; (R16, R17, R21, R22, X)
+  rcall uartBitbang_SendMsg                  ; (R16, R17, R21, R22, R24, R25, X)
-  brcc uartBitBang_sendNextPkg_error
+  brcc uartBitBang_sendNextPkg_end
   rcall NET_Interface_GetNextOutgoingMsgNum  ; remove from stack (R17, R18, X)
   rcall NET_Buffer_ReleaseByNum              ; release buffer (R16, X)
-  ldi r16, NET_IFACE_OFFS_PACKETSOUT_LOW
-  rcall NET_Interface_IncCounter16           ; (R24, R25)
   sec
   rjmp uartBitBang_sendNextPkg_end
-uartBitBang_sendNextPkg_error:
-  rcall NET_Interface_IncCounter16           ; (R24, R25)
 uartBitBang_sendNextPkg_end:
   ret
 ; @end

avr/modules/uart_bitbang2/msglevel.asm

@@ -128,16 +128,38 @@ uartBitbang_RawReceiveMsg_end:
 ; @param  X ptr to buffer to send
 ; @return CFLAGS set if okay, cleared otherwise (index of error variable in R16)
 ; @return R16 index of error variable (if CFLAGS cleared)
-; @clobbers R16, R22 (R17, R21, X)
+; @clobbers R16 (R17, R21, R22, R24, R25, X)
 
 uartBitbang_SendMsg:
   rcall uartBitbang_AcquireBus
   brcc uartBitbang_SendMsg_lineBusyError
 
-  rcall uartBitbang_WaitForOneBitLength          ; wait for one bit duration (R22)
   rcall uartBitbang_WaitForOneBitLength          ; wait for one bit duration (R22)
   rcall uartBitbang_WaitForOneBitLength          ; wait for one bit duration (R22)
 
+  rcall uartBitbang_RawSendMsg                   ; (R16, R17, R21, R22, R24, R25, X)
+  cbi COM_ATTN_DDR, COM_ATTN_PIN                 ; release ATTN line (by setting direction to IN)
+  ret
+uartBitbang_SendMsg_lineBusyError:
+  ldi r16, NET_IFACE_OFFS_ERR_BUSY_LOW
+  rcall NET_Interface_IncCounter16               ; (R24, R25)
+  clc
+  ret
+; @end
+
+
+
+; ---------------------------------------------------------------------------
+; @routine uartBitbang_RawSendMsg
+;
+; Send packet over wire.
+;
+; @param  X ptr to buffer to send
+; @return CFLAGS set if okay, cleared otherwise (index of error variable in R16)
+; @return R16 index of error variable (if CFLAGS cleared)
+; @clobbers R16, R17 (R21, R22, R24, R25, X)
+
+uartBitbang_RawSendMsg:
   adiw xh:xl, NETMSG_OFFS_MSGLEN
   ld r17, X
   sbiw xh:xl, NETMSG_OFFS_MSGLEN
@@ -145,25 +167,68 @@ uartBitbang_SendMsg:
   inc r17                                        ; account for msglen byte
   inc r17                                        ; account for crc byte
 
-uartBitbang_SendMsg_loop:
+uartBitbang_RawSendMsg_loop:
     rcall uartBitbang_WaitForOneBitLength        ; wait for one bit duration (R22)
 
     ld r16, X+
     rcall uartBitbang_SendByte                   ; send byte (R16, R21, R22)
-    brcc uartBitbang_SendMsg_releaseBusRet
+    brcc uartBitbang_RawSendMsg_ioError
     dec r17
-  brne uartBitbang_SendMsg_loop
+  brne uartBitbang_RawSendMsg_loop
+  ldi r16, NET_IFACE_OFFS_PACKETSOUT_LOW
+  rcall NET_Interface_IncCounter16               ; (R24, R25)
   sec
-uartBitbang_SendMsg_releaseBusRet:
-  cbi COM_ATTN_DDR, COM_ATTN_PIN                 ; release ATTN line (by setting direction to IN)
-  brcc uartBitbang_SendMsg_ioError
-  ; packet successfully sent
   ret
-uartBitbang_SendMsg_ioError:
+uartBitbang_RawSendMsg_ioError:
   ldi r16, NET_IFACE_OFFS_ERR_COLLISIONS_LOW
+  rcall NET_Interface_IncCounter16               ; (R24, R25)
+  clc
   ret
-uartBitbang_SendMsg_lineBusyError:
+; @end
-  ldi r16, NET_IFACE_OFFS_ERR_BUSY_LOW
+
+
+
+
+
+; ---------------------------------------------------------------------------
+; @routine uartBitbang_WaitForAttnHigh
+;
+; Wait up to 1ms for data pin to become high
+; @return CFLAG set if okay, clear otherwise
+; @clobbers R17, R22
+
+uartBitbang_WaitForAttnHigh:
+  cbi COM_ATTN_DDR, COM_ATTN_PIN          ; set ATTN port as input
+  cbi COM_ATTN_OUTPUT, COM_ATTN_PIN       ; disable internal pullup for ATTN
+  UART_BB_M_WAIT_FOR_PIN_HIGH COM_ATTN_INPUT, COM_ATTN_PIN
+  ret
+; @end
+
+
+
+
+; ---------------------------------------------------------------------------
+; @routine uartBitbang_AcquireBus
+;
+; Reserve bus if free (otherwise return error)
+; Expects interrupts to be disabled.
+;
+; @return CFLAG set if okay (bus acquired), cleared on error
+; @clobbers: none
+
+uartBitbang_AcquireBus:
+  ; check for ATTN line: busy?
+  cbi COM_ATTN_DDR, COM_ATTN_PIN                 ; set ATTN as input
+  cbi COM_ATTN_OUTPUT, COM_ATTN_PIN              ; disable pullup on ATTN
+  nop                                            ; needed to sample current input
+  sbis COM_ATTN_INPUT, COM_ATTN_PIN              ; ATTN low?
+    rjmp uartBitbang_AcquireBus_busy             ; jump if it is
+  sbi COM_ATTN_DDR, COM_ATTN_PIN                 ; set ATTN as output
+  cbi COM_ATTN_OUTPUT, COM_ATTN_PIN              ; set ATTN low
+  sec
+  ret
+uartBitbang_AcquireBus_busy:
+  clc
   ret
 ; @end