avr: make COM2 buffer functions macros.

avr/modules/com2/buffer.asm

@@ -9,136 +9,167 @@
 
 
 
+; ===========================================================================
+;
+; Macros for working with message buffers.
+;
+; Helpfull defines:
+; - COM2_BUFFER_NUM  number of buffers to provide
+; - COM2_BUFFER_SIZE size of each buffer (CAVE: change COM2_M_BufferPosToX when changing value!)
+;
+; Variables:
+; - buffersUsed:     .byte 1   holds number of buffers in use
+; - maxBuffersUsed:  .byte 1   holds max number of buffers every in use at the same time
+; - buffersWritePos: .byte 1   holds current write pos
+; - buffersReadPos:  .byte 1   holds current read pos
+; - buffers:         .byte COM2_BUFFER_SIZE*COM2_BUFFER_NUM
+
+
 
 ; ---------------------------------------------------------------------------
-; COM_BufferAlloc
+; @macro COM2_M_BufferAlloc
 ;
-; Allocate a transfer buffer.
+; Allocate a message buffer.
-; IN:
+;
-; - nothing
+; COM2_M_BufferAlloc COM2_BUFFER_NUM, com2MaxBuffersUsed, com2RecvBuffersUsed, com2RecvBuffersWritePos
-; OUT:
+;
-; - CFLAG: set if okay, clear otherwise
+; @param %0 max number of buffers
-; - X: pointer to allocated buffer in SRAM
+; @param %1 pointer to byte containing max number of buffers ever used
-; MODIFIED REGISTERS: r16, r17, r21
+; @param %2 pointer to byte containing number of buffers currently in use
+; @param %3 pointer to byte containing the write pointer
+; @return CFLAG set if okay, clear otherwise
+; @return X pos to allocated buffer
+; @clobbers R16, R17, R21
 
-
+.macro COM2_M_BufferAlloc
-COM2_BufferAlloc:
+  in r21, SREG              ; save global interrupt enable bit from SREG
-  in r21, SREG                            ; save global interrupt enable bit from SREG
   cli
-  lds r17, com2RecvBuffersUsed
+  lds r17, @2
-  cpi r17, COM2_BUFFER_NUM
+  cpi r17, @0
-  brcc COM2_AllocBuffer_error             ; no buffer available
+  brcc l_error              ; no buffer available
-  inc r17                                 ; increment number of buffers used
+  inc r17                   ; increment number of buffers used
-  sts com2RecvBuffersUsed, r17            ; store new value
+  sts @2, r17               ; store new value
-  lds r16, com2MaxBuffersUsed             ; calc max buffers used
+  lds r16, @1               ; calc max buffers used
   cp r16, r17
-  brcc COM2_AllocBuffer_l0
+  brcc l0
-  sts com2MaxBuffersUsed, r17
+  sts @1, r17
-COM2_AllocBuffer_l0:
+l0:
-  lds r16, com2RecvBuffersWritePos        ; get current write pos
+  lds r16, @3               ; get current write pos
-  mov r17, r16                            ; increment for next call
+  mov r17, r16              ; increment for next call
   inc r17
-  cpi r17, COM2_BUFFER_NUM                ; CF set if COM_BUFFER_NUM > R17
+  cpi r17, @0               ; CF set if COM_BUFFER_NUM > R17
-  brcs COM2_AllocBuffer_l1
+  brcs l1
-  clr r17                                 ; wraparound
+  clr r17                   ; wraparound
-COM2_AllocBuffer_l1:
+l1:
-  sts com2RecvBuffersWritePos, r17        ; store new writepos for next caller
+  sts @3, r17               ; store new writepos for next caller
-  rcall COM2_BufferPosToX                 ; (R16, R17)
+  rcall COM2_BufferPosToX   ; (R16, R17)
-  out SREG, r21                           ; restore global interrupt enable bit in SREG
+  out SREG, r21             ; restore global interrupt enable bit in SREG
   sec
-  ret
+  rjmp l_end
-COM2_AllocBuffer_error:
+l_error:
   out SREG, r21
   clc
-  ret
+l_end:
+.endmacro
+; @end
 
 
 
 ; ---------------------------------------------------------------------------
-; COM2_BufferDeallocBack
+; @macro COM2_M_BufferDeallocBack
 ;
 ; Release a transfer buffer at the end of the list by decreasing the write pos.
 ; This releases the last allocated buffer!
 ;
-; IN:
+; COM2_M_BufferDeallocBack COM2_BUFFER_NUM, com2RecvBuffersUsed, com2RecvBuffersWritePos
-; - nothing
+;
-; OUT:
+; @param %0 maximum number of buffers
-; - CFLAG: set if okay, clear otherwise
+; @param %1 pointer to a byte containing number of buffers used
-; MODIFIED REGISTERS: r16, r17, r21
+; @param %2 pointer to a byte containing current write pos
+; @return CFLAG set if okay, clear otherwise
+; @clobbers r16, r17, r21
 
-COM2_BufferDeallocBack:
+.macro COM2_M_BufferDeallocBack
-  in r21, SREG                            ; save global interrupt enable bit from SREG
+  in r21, SREG       ; save global interrupt enable bit from SREG
   cli
-  lds r17, com2RecvBuffersUsed
+  lds r17, @1
   tst r17
-  breq COM2_BufferDeallocBack_error       ; no buffer allocated, nothing to release
+  breq l_error       ; no buffer allocated, nothing to release
   dec r17
-  sts com2RecvBuffersUsed, r17            ; store new value
+  sts @1, r17        ; store new value
-  lds r17, com2RecvBuffersWritePos
+  lds r17, @2
-  tst r17                                 ; 0?
+  tst r17            ; 0?
-  brne COM2_BufferDeallocBack_l1          ; nope go directly decrement r17
+  brne l1            ; nope go directly decrement r17
-  ldi r17, COM2_BUFFER_NUM                ; wrap-around
+  ldi r17, @0        ; wrap-around
-COM2_BufferDeallocBack_l1:
+l1:
   dec r17
-  sts com2RecvBuffersWritePos, r17
+  sts @2, r17
   out SREG, r21
   sec
-  ret
+  rjmp l_end
-COM2_BufferDeallocBack_error:
+l_error:
   out SREG, r21
   clc
-  ret
+l_end:
+.endmacro
+; @end
 
 
 
 ; ---------------------------------------------------------------------------
-; COM2_BufferDeallocFront
+; @macro COM2_M_BufferDeallocFront
 ;
 ; Release a transfer buffer by increasing the read pos.
 ;
-; IN:
+; COM2_M_BufferDeallocFront COM2_BUFFER_NUM com2RecvBuffersUsed com2RecvBuffersReadPos
-; - nothing
+;
-; OUT:
+; @param %0 maximum number of buffers
-; - CFLAG: set if okay, clear otherwise
+; @param %1 pointer to a byte containing number of buffers used
-; MODIFIED REGISTERS: r16, r17, r21
+; @param %2 pointer to a byte containing current read pos
+; @return CFLAG set if okay, clear otherwise
+; @clobbers r16, r17, r21
 
-COM2_BufferDeallocFront:
+.macro COM2_M_BufferDeallocFront
-  in r21, SREG                           ; save global interrupt enable bit from SREG
+  in r21, SREG     ; save global interrupt enable bit from SREG
   cli
-  lds r17, com2RecvBuffersUsed
+  lds r17, @1
   tst r17
-  breq COM2_BufferDeallocFront_error     ; no buffer allocated, nothing to release
+  breq l_error     ; no buffer allocated, nothing to release
   dec r17
-  sts com2RecvBuffersUsed, r17            ; store new value
+  sts @1, r17      ; store new value
-  lds r17, com2RecvBuffersReadPos
+  lds r17, @2
   inc r17
-  cpi r17, COM2_BUFFER_NUM
+  cpi r17, @0
-  brcs COM2_BufferDeallocFront_l1
+  brcs l1
-  clr r17                                ; wrap-around
+  clr r17          ; wrap-around
-COM2_BufferDeallocFront_l1:
+l1:
-  sts com2RecvBuffersReadPos, r17
+  sts @2, r17
   out SREG, r21
   sec
-  ret
+  rjmp l_end
-COM2_BufferDeallocFront_error:
+l_error:
   out SREG, r21
   clc
-  ret
+l_end:
+.endmacro
+; @end
 
 
 
 ; ---------------------------------------------------------------------------
-; COM2_BufferPosToX
+; @macro COM2_M_BufferPosToX
 ;
 ; Get a pointer to the SRAM position of the given buffer.
 ; CAVE: Code must correspond to COM2_BUFFER_SIZE!!
-; IN:
+;
-; - R16: buffer number (starting with 0)
+; COM2_M_BufferPosToX com2RecvBuffers
-; OUT:
+;
-; - X: pointer to buffer in SRAM
+; @param %0 pointer to a 2 byte var containing pointer to buffers
-; MODIFIED REGISTERS: R16, R17
+; @param  R16 buffer number (starting with 0)
+; @return X   pointer to buffer in SRAM
+; @clobbers R16, R17
 
-COM2_BufferPosToX:
+.macro COM2_M_BufferPosToX
   ; calculate offset
   clr r17
   mov xl, r16
@@ -160,11 +191,12 @@ COM2_BufferPosToX:
   rol xh ; *24
 
   ; add base position of buffers
-  ldi r16, LOW(com2RecvBuffers)
+  ldi r16, LOW(@0)
-  ldi r17, HIGH(com2RecvBuffers)
+  ldi r17, HIGH(@0)
   add xl, r16
   adc xh, r17
-  ret
+.endmacro
+; @end
 
 
 

avr/modules/com2/main.asm

@@ -8,6 +8,9 @@
 ; ***************************************************************************
 
 
+.include "modules/com2/buffer.asm"
+
+
 
 ; ***************************************************************************
 ; data
@@ -19,6 +22,7 @@ com2DataBegin:
   com2Address:             .byte 1
 
   com2Interrupts:          .byte 2
+  com2LastMsgId:           .byte 2
 
 com2RecvStatsBegin:        ; 12 bytes
   com2StatsPacketsIn:      .byte 2
@@ -26,7 +30,6 @@ com2RecvStatsBegin:        ; 12 bytes
   com2StatsIoError:        .byte 2
   com2StatsNoBufferError:  .byte 2
   com2StatsHandled:        .byte 2
-  com2StatsNotForMe:       .byte 2
   com2StatsMissed:         .byte 2   ; currently not used
 com2RecvStatsEnd:
 
@@ -36,6 +39,7 @@ com2SendStatsBegin:        ; 6 bytes
   com2StatsBusyError:      .byte 2
 com2SendStatsEnd:
 
+  com2StatsNotForMe:       .byte 2
   com2StatsIgnored:        .byte 2
   
   com2RecvBuffersUsed:     .byte 1
@@ -399,6 +403,78 @@ COM2_SendPacket_okay:
 
 
 
+
+
+; +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+; Buffer Management
+; +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+
+; ---------------------------------------------------------------------------
+; @routine COM2_BufferAlloc
+;
+; Allocate a transfer buffer.
+;
+; @return CFLAG set if okay, clear otherwise
+; @return X     pointer to allocated buffer in SRAM
+; @clobbers r16, r17, r21
+
+COM2_BufferAlloc:
+  COM2_M_BufferAlloc COM2_BUFFER_NUM, com2MaxBuffersUsed, com2RecvBuffersUsed, com2RecvBuffersWritePos
+  ret
+; @end
+
+
+
+; ---------------------------------------------------------------------------
+; @routine COM2_BufferDeallocBack
+;
+; Release a transfer buffer at the end of the list by decreasing the write pos.
+; This releases the last allocated buffer!
+;
+; @return CFLAG set if okay, clear otherwise
+; @clobbers r16, r17, r21
+
+COM2_BufferDeallocBack:
+  COM2_M_BufferDeallocBack COM2_BUFFER_NUM, com2RecvBuffersUsed, com2RecvBuffersWritePos
+  ret
+; @end
+
+
+
+; ---------------------------------------------------------------------------
+; @routine COM2_BufferDeallocFront
+;
+; Release a transfer buffer by increasing the read pos.
+;
+; @return CFLAG set if okay, clear otherwise
+; @clobbers r16, r17, r21
+
+COM2_BufferDeallocFront:
+  COM2_M_BufferDeallocFront COM2_BUFFER_NUM, com2RecvBuffersUsed, com2RecvBuffersReadPos
+  ret
+; @end
+
+
+
+; ---------------------------------------------------------------------------
+; @routine COM2_BufferPosToX
+;
+; Get a pointer to the SRAM position of the given buffer.
+; CAVE: Code must correspond to COM2_BUFFER_SIZE!!
+;
+; @param  R16 buffer number (starting with 0)
+; @return X   pointer to buffer in SRAM
+; @clobbers R16, R17
+
+COM2_BufferPosToX:
+  COM2_M_BufferPosToX com2RecvBuffers
+  ret
+; @end
+
+
+
+
+
 ; +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 ; ISR
 ; +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
@@ -451,7 +527,6 @@ com2IsrPcint0_end:
 
 .include "modules/com2/packets.asm"
 .include "modules/com2/lowlevel.asm"
-.include "modules/com2/buffer.asm"
 .include "modules/com2/crc.asm"