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Take in account that the C64 Retro Replay clockport needs to be activated in order to work with the RR-Net Ethernet card.

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oliverschmidt 2007-12-08 21:05:48 +00:00
parent 32ae3317a6
commit a980f40bf6
1 changed files with 59 additions and 49 deletions
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108
cpu/6502/net/cs8900a.S
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@ -30,7 +30,7 @@
;
; Author: Adam Dunkels <adam@sics.se>, Oliver Schmidt <ol.sc@web.de>
;
; $Id: cs8900a.S,v 1.3 2007/11/29 21:56:55 oliverschmidt Exp $
; $Id: cs8900a.S,v 1.4 2007/12/08 21:05:48 oliverschmidt Exp $
;
;---------------------------------------------------------------------
@ -89,6 +89,7 @@ fixup: .byte fixup02-fixup01, fixup03-fixup02, fixup04-fixup03
.byte fixup38-fixup37, fixup39-fixup38, fixup40-fixup39
.byte fixup41-fixup40, fixup42-fixup41, fixup43-fixup42
.byte fixup44-fixup43, fixup45-fixup44, fixup46-fixup45
.byte fixup47-fixup46, fixup48-fixup47
fixups = * - fixup
@ -97,6 +98,7 @@ fixups = * - fixup
rxtxreg := $FF00 ; High byte patched at runtime
txcmd := $FF04 ; High byte patched at runtime
txlen := $FF06 ; High byte patched at runtime
isq := $FF08 ; High byte patched at runtime
packetpp := $FF0A ; High byte patched at runtime
ppdata := $FF0C ; High byte patched at runtime
@ -138,56 +140,64 @@ init:
inc ptr+1
bcs :- ; Always
: Activate C64 RR clockport in order to operate RR-Net
; - RR config register overlays CS8900A ISQ register
; - No need to distinguish as ISQ access doesn't hurt
:
fixup01:lda isq+1
ora #$01 ; Set clockport bit
fixup02:sta isq+1
; Turn on transmission and reception of frames
; PACKETPP = $0112, PPDATA = $00C0
: lda #$12
lda #$12
ldx #$01
fixup01:sta packetpp
fixup02:stx packetpp+1
fixup03:sta packetpp
fixup04:stx packetpp+1
lda #$C0
ldx #$00
fixup03:sta ppdata
fixup04:stx ppdata+1
fixup05:sta ppdata
fixup06:stx ppdata+1
; Accept valid unicast + broadcast frames
; PACKETPP = $0104, PPDATA = $0D05
lda #$04
ldx #$01
fixup05:sta packetpp
fixup06:stx packetpp+1
fixup07:sta packetpp
fixup08:stx packetpp+1
lda #$05
ldx #$0D
fixup07:sta ppdata
fixup08:stx ppdata+1
fixup09:sta ppdata
fixup10:stx ppdata+1
; Set MAC address
; PACKETPP = $0158, PPDATA = MAC[0], MAC[1]
lda #$58
ldx #$01
fixup09:sta packetpp
fixup10:stx packetpp+1
fixup11:sta packetpp
fixup12:stx packetpp+1
lda mac
ldx mac+1
fixup11:sta ppdata
fixup12:stx ppdata+1
fixup13:sta ppdata
fixup14:stx ppdata+1
; PACKETPP = $015A, PPDATA = MAC[2], MAC[3]
lda #$5A
ldx #$01
fixup13:sta packetpp
fixup14:stx packetpp+1
fixup15:sta packetpp
fixup16:stx packetpp+1
lda mac+2
ldx mac+3
fixup15:sta ppdata
fixup16:stx ppdata+1
fixup17:sta ppdata
fixup18:stx ppdata+1
; PACKETPP = 0x015C, PPDATA = MAC[4], MAC[5]
lda #$5C
ldx #$01
fixup17:sta packetpp
fixup18:stx packetpp+1
fixup19:sta packetpp
fixup20:stx packetpp+1
lda mac+4
ldx mac+5
fixup19:sta ppdata
fixup20:stx ppdata+1
fixup21:sta ppdata
fixup22:stx ppdata+1
rts
;---------------------------------------------------------------------
@ -198,9 +208,9 @@ poll:
; PACKETPP = $0124, PPDATA & $0D00 ?
lda #$24
ldx #$01
fixup21:sta packetpp
fixup22:stx packetpp+1
fixup23:lda ppdata+1
fixup23:sta packetpp
fixup24:stx packetpp+1
fixup25:lda ppdata+1
and #$0D
bne :+
@ -214,13 +224,13 @@ fixup23:lda ppdata+1
; Read receiver event and discard it
; RXTXREG
:
fixup24:ldx rxtxreg+1
fixup25:lda rxtxreg
fixup26:ldx rxtxreg+1
fixup27:lda rxtxreg
; Read frame length
; cnt = len = RXTXREG
fixup26:ldx rxtxreg+1
fixup27:lda rxtxreg
fixup28:ldx rxtxreg+1
fixup29:lda rxtxreg
sta len
stx len+1
sta cnt
@ -245,11 +255,11 @@ fixup27:lda rxtxreg
; PACKETPP = $0102, PPDATA = PPDATA | $0040
lda #$02
ldx #$01
fixup28:sta packetpp
fixup29:stx packetpp+1
fixup30:lda ppdata
fixup30:sta packetpp
fixup31:stx packetpp+1
fixup32:lda ppdata
ora #$40
fixup31:sta ppdata
fixup33:sta ppdata
; No frame ready
lda #$00
@ -264,10 +274,10 @@ fixup31:sta ppdata
ldx cnt+1
ldy #$00
read:
fixup32:lda rxtxreg
fixup34:lda rxtxreg
sta (ptr),y
iny
fixup33:lda rxtxreg+1
fixup35:lda rxtxreg+1
sta (ptr),y
iny
bne :+
@ -276,7 +286,7 @@ fixup33:lda rxtxreg+1
bne read
dex
bpl read
; Return frame length
lda len
ldx len+1
@ -292,12 +302,12 @@ send:
; Transmit command
lda #$C0
ldx #$00
fixup34:sta txcmd
fixup35:stx txcmd+1
fixup36:sta txcmd
fixup37:stx txcmd+1
lda cnt
ldx cnt+1
fixup36:sta txlen
fixup37:stx txlen+1
fixup38:sta txlen
fixup39:stx txlen+1
; Adjust odd frame length
lsr
@ -313,9 +323,9 @@ fixup37:stx txlen+1
; PACKETPP = $0138, PPDATA & $0100 ?
: lda #$38
ldx #$01
fixup38:sta packetpp
fixup39:stx packetpp+1
fixup40:lda ppdata+1
fixup40:sta packetpp
fixup41:stx packetpp+1
fixup42:lda ppdata+1
and #$01
bne :+
@ -323,11 +333,11 @@ fixup40:lda ppdata+1
; PACKETPP = $0102, PPDATA = PPDATA | $0040
lda #$02
ldx #$01
fixup41:sta packetpp
fixup42:stx packetpp+1
fixup43:lda ppdata
fixup43:sta packetpp
fixup44:stx packetpp+1
fixup45:lda ppdata
ora #$40
fixup44:sta ppdata
fixup46:sta ppdata
; And try again
dey
@ -345,10 +355,10 @@ fixup44:sta ppdata
ldx cnt+1
ldy #$00
write: lda (ptr),y
fixup45:sta rxtxreg
fixup47:sta rxtxreg
iny
lda (ptr),y
fixup46:sta rxtxreg+1
fixup48:sta rxtxreg+1
iny
bne :+
inc ptr+1