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recipe/rc2014/sdcard: we got out of initialization!

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This commit is contained in:
Virgil Dupras 2019-05-07 16:38:08 -04:00
parent c9f164a510
commit beeb40eb93
1 changed files with 27 additions and 0 deletions
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27
recipes/rc2014/sdcard/sdinit.asm
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@ -38,6 +38,31 @@
jr nz, .error
ld hl, sOk
call JUMP_PRINTSTR
; Now we need to repeatedly run CMD55+CMD41 (0x40000000) until we
; the card goes out of idle mode, that is, when it stops sending us
; 0x01 response and send us 0x00 instead. Any other response means that
; initialization failed.
ld hl, sCmd41
call JUMP_PRINTSTR
.loop:
ld a, 0b01110111 ; CMD55
ld hl, 0
ld de, 0
call JUMP_SDCCMDR1
cp 0x01
jr nz, .error
ld a, 0b01101001 ; CMD41 (0x40000000)
ld hl, 0x4000
ld de, 0x0000
call JUMP_SDCCMDR1
cp 0x01
jr z, .loop
cp 0
jr nz, .error
; Success! out of idle mode!
ld hl, sOk
call JUMP_PRINTSTR
ret
.error:
ld hl, sErr
@ -48,6 +73,8 @@ sCmd0:
.db "Sending CMD0", 0xa, 0xd, 0
sCmd8:
.db "Sending CMD8", 0xa, 0xd, 0
sCmd41:
.db "Sending CMD41", 0xa, 0xd, 0
sOk:
.db "Ok", 0xa, 0xd, 0
sErr: