mirror of
https://github.com/hsoft/collapseos.git
synced 2024-12-26 03:38:06 +11:00
sdc: allow the read of 0xff
That took an embarrasingly large amount of time to debug for something, in the end, so obvious...
This commit is contained in:
parent
2e8af376e3
commit
3bc7cec03a
@ -63,14 +63,17 @@ sdcSendRecv:
|
|||||||
nop
|
nop
|
||||||
ret
|
ret
|
||||||
|
|
||||||
|
sdcIdle:
|
||||||
|
ld a, 0xff
|
||||||
|
jp sdcSendRecv
|
||||||
|
|
||||||
; sdcSendRecv 0xff until the response is something else than 0xff for a maximum
|
; sdcSendRecv 0xff until the response is something else than 0xff for a maximum
|
||||||
; of 20 times. Returns 0xff if no response.
|
; of 20 times. Returns 0xff if no response.
|
||||||
sdcWaitResp:
|
sdcWaitResp:
|
||||||
push bc
|
push bc
|
||||||
ld b, 20
|
ld b, 20
|
||||||
.loop:
|
.loop:
|
||||||
ld a, 0xff
|
call sdcIdle
|
||||||
call sdcSendRecv
|
|
||||||
inc a ; if 0xff, it's going to become zero
|
inc a ; if 0xff, it's going to become zero
|
||||||
jr nz, .end ; not zero? good, that's our command
|
jr nz, .end ; not zero? good, that's our command
|
||||||
djnz .loop
|
djnz .loop
|
||||||
@ -286,14 +289,14 @@ sdcReadBlk:
|
|||||||
ld bc, SDC_BLKSIZE
|
ld bc, SDC_BLKSIZE
|
||||||
ld hl, SDC_BUF
|
ld hl, SDC_BUF
|
||||||
.loop2:
|
.loop2:
|
||||||
call sdcWaitResp
|
call sdcIdle
|
||||||
ld (hl), a
|
ld (hl), a
|
||||||
cpi ; a trick to inc HL and dec BC at the same time.
|
cpi ; a trick to inc HL and dec BC at the same time.
|
||||||
; P/V indicates whether BC reached 0
|
; P/V indicates whether BC reached 0
|
||||||
jp pe, .loop2 ; BC is not zero, loop
|
jp pe, .loop2 ; BC is not zero, loop
|
||||||
; Read our 2 CRC bytes
|
; Read our 2 CRC bytes
|
||||||
call sdcWaitResp
|
call sdcIdle
|
||||||
call sdcWaitResp
|
call sdcIdle
|
||||||
; success! Let's recall our orginal A arg and put it in SDC_BUFSEC
|
; success! Let's recall our orginal A arg and put it in SDC_BUFSEC
|
||||||
ld a, e
|
ld a, e
|
||||||
ld (SDC_BUFSEC), a
|
ld (SDC_BUFSEC), a
|
||||||
|
Loading…
Reference in New Issue
Block a user