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Merge pull request #419 from oliverschmidt/master

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Saved six more bytes ;-)
This commit is contained in:
Oliver Schmidt 2013-11-13 14:43:06 -08:00
commit 59c28bc32b
1 changed files with 38 additions and 36 deletions
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74
cpu/6502/net/cs8900a.S
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@ -73,8 +73,6 @@ fixup: .byte fixup02-fixup01, fixup03-fixup02, fixup04-fixup03
.byte fixup14-fixup13, fixup15-fixup14, fixup16-fixup15
.byte fixup17-fixup16, fixup18-fixup17, fixup19-fixup18
.byte fixup20-fixup19, fixup21-fixup20, fixup22-fixup21
.byte fixup23-fixup22, fixup24-fixup23, fixup25-fixup24
.byte fixup26-fixup25
fixups = * - fixup
@ -112,7 +110,7 @@ init:
lda reg+1
sta (ptr),y
dey
; Advance to next fixup location
inx
cpx #fixups
@ -136,11 +134,10 @@ fixup02:sta isq+1
; Accept valid unicast + broadcast frames
; PACKETPP = $0104, PPDATA = $0D05
lda #$04
jsr packetpp_01
jsr packetpp_a1
lda #$05
ldx #$0D
fixup03:sta ppdata
fixup04:stx ppdata+1
jsr ppdata_ax
; Set MAC address
; PACKETPP = $0158, PPDATA = MAC[0], MAC[1]
@ -148,11 +145,10 @@ fixup04:stx ppdata+1
; PACKETPP = $015C, PPDATA = MAC[4], MAC[5]
ldy #$58
: tya
jsr packetpp_01
jsr packetpp_a1
lda mac-$58,y
ldx mac-$58+1,y
fixup05:sta ppdata
fixup06:stx ppdata+1
jsr ppdata_ax
iny
iny
cpy #$58+6
@ -161,11 +157,10 @@ fixup06:stx ppdata+1
; Turn on transmission and reception of frames
; PACKETPP = $0112, PPDATA = $00D3
lda #$12
jsr packetpp_01
jsr packetpp_a1
lda #$D3
ldx #$00
fixup07:sta ppdata
fixup08:stx ppdata+1
jsr ppdata_ax
rts
;---------------------------------------------------------------------
@ -175,11 +170,11 @@ poll:
; are any valid unicast frames avaliable
; PACKETPP = $0124, PPDATA & $0D00 ?
lda #$24
jsr packetpp_01
fixup09:lda ppdata+1
jsr packetpp_a1
fixup03:lda ppdata+1
and #$0D
bne :+
; No frame ready
tax
rts
@ -190,13 +185,13 @@ fixup09:lda ppdata+1
; Read receiver event and discard it
; RXTXREG
:
fixup10:ldx rxtxreg+1
fixup11:lda rxtxreg
fixup04:ldx rxtxreg+1
fixup05:lda rxtxreg
; Read frame length
; cnt = len = RXTXREG
fixup12:ldx rxtxreg+1
fixup13:lda rxtxreg
fixup06:ldx rxtxreg+1
fixup07:lda rxtxreg
sta len
stx len+1
sta cnt
@ -223,10 +218,10 @@ fixup13:lda rxtxreg
; Read bytes into buffer
: jsr adjustptr
:
fixup14:lda rxtxreg
fixup08:lda rxtxreg
sta (ptr),y
iny
fixup15:lda rxtxreg+1
fixup09:lda rxtxreg+1
sta (ptr),y
iny
bne :-
@ -249,12 +244,12 @@ send:
; Transmit command
lda #$C9
ldx #$00
fixup16:sta txcmd
fixup17:stx txcmd+1
fixup10:sta txcmd
fixup11:stx txcmd+1
lda cnt
ldx cnt+1
fixup18:sta txlen
fixup19:stx txlen+1
fixup12:sta txlen
fixup13:stx txlen+1
; Adjust odd frame length
jsr adjustcnt
@ -265,8 +260,8 @@ fixup19:stx txlen+1
; Check for avaliable buffer space
; PACKETPP = $0138, PPDATA & $0100 ?
: lda #$38
jsr packetpp_01
fixup20:lda ppdata+1
jsr packetpp_a1
fixup14:lda ppdata+1
and #$01
bne :+
@ -284,10 +279,10 @@ fixup20:lda ppdata+1
; Write bytes from buffer
: jsr adjustptr
: lda (ptr),y
fixup21:sta rxtxreg
fixup15:sta rxtxreg
iny
lda (ptr),y
fixup22:sta rxtxreg+1
fixup16:sta rxtxreg+1
iny
bne :-
inc ptr+1
@ -302,10 +297,17 @@ exit:
;---------------------------------------------------------------------
packetpp_01:
packetpp_a1:
ldx #$01
fixup23:sta packetpp
fixup24:stx packetpp+1
fixup17:sta packetpp
fixup18:stx packetpp+1
rts
;---------------------------------------------------------------------
ppdata_ax:
fixup19:sta ppdata
fixup20:stx ppdata+1
rts
;---------------------------------------------------------------------
@ -313,10 +315,10 @@ fixup24:stx packetpp+1
skipframe:
; PACKETPP = $0102, PPDATA = PPDATA | $0040
lda #$02
jsr packetpp_01
fixup25:lda ppdata
jsr packetpp_a1
fixup21:lda ppdata
ora #$40
fixup26:sta ppdata
fixup22:sta ppdata
rts
;---------------------------------------------------------------------