This commit is contained in:
lampmerchant 2021-11-28 10:29:06 -07:00
parent c3972c370b
commit 3144494de5

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@ -89,6 +89,7 @@ M_CMDRB equ 5 ;Set when an R1b is expected (busy signal after reply)
M_MBRD equ 4 ;Set when a multiblock read is in progress
M_MBWR equ 3 ;Set when a multiblock write is in progress
M_BKADR equ 2 ;Set when block (rather than byte) addressing is in use
M_CDVER equ 1 ;Set when dealing with a V2.0+ card, clear for 1.0
;DVxFLAG:
DV_EXST equ 7 ;Set when device exists
@ -97,7 +98,7 @@ DV_EXST equ 7 ;Set when device exists
FWVER_3 equ 0x20
FWVER_2 equ 0x21
FWVER_1 equ 0x11
FWVER_0 equ 0x26
FWVER_0 equ 0x28
;;; Variable Storage ;;;
@ -114,9 +115,9 @@ FWVER_0 equ 0x26
M_ADR2 ;Second byte of the address, second byte of R3/R7 response
M_ADR1 ;Third byte of the address, third byte of R3/R7 response
M_ADR0 ;Fourth (low) byte of the address, last byte of R3/R7 response
M_CRC ;CRC byte of the command to be sent
TEMP ;Various purposes
TEMP2 ;Various purposes
D3
D2
D1
D0
@ -193,15 +194,17 @@ FWVER_0 equ 0x26
LOG_1E
LOG_1F
;TODO Unused 8 bytes
UNUSED0
UNUSED1
UNUSED2
UNUSED3
UNUSED4
UNUSED5
;Card info
CARDINF
;TODO Unused 7 bytes
UNUSED6
UNUSED7
UNUSED5
UNUSED4
UNUSED3
UNUSED2
UNUSED1
UNUSED0
endc
@ -464,6 +467,8 @@ DelayMs DELAY 242 ; has been done
decfsz TEMP,F ; "
bra DelayMs ; "
call MmcInit ;Initialize!
btfsc M_FLAGS,M_FAIL ;If we couldn't initialize the card, give up
goto NoDevices ; and pass !ENBL through to next device
movlb 4 ;Now that we're initialized, crank the speed
movlw B'00100001' ; of the SPI interface up to 2 MHz
movwf SSPCON1 ; "
@ -665,7 +670,7 @@ CmdRead
clrf TX_PAD2 ; we convert the address since they overlap
clrf TX_PAD3 ; with the address bytes)
;TODO clear 20 tag bytes too?
CmdRea0 movlw 0x51 ;Set up a read command for the MMC card (R1-
movlw 0x52 ;Set up a read command for the MMC card (R1-
movwf M_CMDN ; type response)
bcf M_FLAGS,M_CMDLR ; "
bcf M_FLAGS,M_CMDRB ; "
@ -673,14 +678,19 @@ CmdRea0 movlw 0x51 ;Set up a read command for the MMC card (R1-
call MmcCmd ;Send the MMC command
btfsc M_FLAGS,M_FAIL ;If MMC operation failed, report the error
retlw 0x04 ; "
movlw 0x20 ;Point FSR0 past the six header bytes and the
bsf M_FLAGS,M_MBRD ;Set the flag for an ongoing multiblock read
CmdRea0 movlw 0x20 ;Point FSR0 past the six header bytes and the
movwf FSR0H ; 20 'tag' bytes to where the real data starts
movlw 0x62 ; "
movwf FSR0L ; "
call MmcReadData ;Read data from the MMC card
btfsc M_FLAGS,M_FAIL ;If MMC operation failed, report the error
retlw 0x05 ; "
bsf PORTC,RC3 ;Deassert !CS
decf TX_BLKS,W ;If the blocks-remaining counter is at one,
btfsc STATUS,Z ; stop the multiblock read here before sending
call MmcStopOngoing ; our response to the mac
btfsc M_FLAGS,M_FAIL ;If MMC operation failed, report the error
retlw 0x06 ; "
movlw 77 ;Set the group count to 77 (512 bytes of data,
movwf GROUPS ; 20 'tag' bytes, 6 byte header, checksum byte)
call CalcChecksum ;Calculate the checksum on our response
@ -706,13 +716,13 @@ CmdWrite
bra CmdWriteCont ; "
call MmcStopOngoing ;Stop any multiblock read or write
btfsc M_FLAGS,M_FAIL ;If MMC operation failed, report the error
retlw 0x06 ; "
retlw 0x07 ; "
call TranslateAddr ;Translate block address to MMC block address
btfsc FLAGS,RNFERR ;If we couldn't translate this block address to
retlw 0x07 ; an MMC address, report the error
retlw 0x08 ; an MMC address, report the error
call MmcConvAddr ;Convert the address if necessary
btfsc M_FLAGS,M_FAIL ;If MMC operation failed, report the error
retlw 0x08 ; "
retlw 0x09 ; "
movlw 0x59 ;Set up a write command for the MMC card (R1-
movwf M_CMDN ; type reply)
bcf M_FLAGS,M_CMDLR ; "
@ -720,23 +730,23 @@ CmdWrite
bcf PORTC,RC3 ;Assert !CS
call MmcCmd ;Send the MMC command
btfsc M_FLAGS,M_FAIL ;If MMC operation failed, report the error
retlw 0x09 ; "
retlw 0x0A ; "
bsf M_FLAGS,M_MBWR ;Set the flag for an ongoing multiblock write
CmdWriteCont
btfss M_FLAGS,M_MBWR ;If for some reason we got here without there
retlw 0x0A ; being a multiblock write going on, error
retlw 0x0B ; being a multiblock write going on, error
movlw 0x20 ;Point FSR0 past the sync, length, header, and
movwf FSR0H ; tag bytes, and to the data we'll be writing
movlw 0x65 ; "
movwf FSR0L ; "
call MmcWriteData ;Write data to the MMC card
btfsc M_FLAGS,M_FAIL ;If MMC operation failed, report the error
retlw 0x0B ; "
retlw 0x0C ; "
decf RC_BLKS,W ;If the blocks-remaining counter is at one,
btfsc STATUS,Z ; stop the multiblock write here before sending
call MmcStopOngoing ; our response to the mac
btfsc M_FLAGS,M_FAIL ;If MMC operation failed, report the error
retlw 0x0C ; "
retlw 0x0D ; "
clrf TX_PAD1 ;Clear the padding bytes (don't do this before
clrf TX_PAD2 ; we convert the address since they overlap
clrf TX_PAD3 ; with the address bytes)
@ -991,7 +1001,7 @@ TranslateAddr
;;; MMC Subprograms ;;;
;Initialize MMC card. Sets M_FAIL on fail. Trashes TEMP.
;Initialize MMC card. Sets M_FAIL on fail. Trashes TEMP and TEMP2.
MmcInit
clrf M_FLAGS ;Make sure flags are all clear to begin with
movlb 4 ;This is where all the SSP registers are
@ -1022,8 +1032,40 @@ MmcIni0 movlw 0xFF ; "
bsf M_FLAGS,M_FAIL ; "
btfss STATUS,Z ; "
return ; "
MmcIni1 movlw 0x41 ;Send command 1 (expect R1-type response),
movwf M_CMDN ; which tells the card to initialize
bsf M_FLAGS,M_CDVER ;Assume version 2.0+ to begin with
clrf TEMP ;Set retry counter to 0 (65536) for later use
clrf TEMP2 ; "
movlw 0x48 ;Send command 8 (expect R7-type response) to
movwf M_CMDN ; check if we're dealing with a V2.0+ card
clrf M_ADR3 ; "
clrf M_ADR2 ; "
movlw 0x01 ; "
movwf M_ADR1 ; "
movlw 0xAA ; "
movwf M_ADR0 ; "
bsf M_FLAGS,M_CMDLR ; "
bcf M_FLAGS,M_CMDRB ; "
call MmcCmd ; "
movf M_CMDN,W ;If the command set any error flags or there
andlw B'11111110' ; was no response, switch assumptions and guess
btfsc STATUS,Z ; that we're dealing with a Version 1 card and
btfsc M_FLAGS,M_FAIL ; jump ahead to initialize it
bcf M_FLAGS,M_CDVER ; "
btfss M_FLAGS,M_CDVER ; "
bra MmcIni1 ; "
movf M_ADR1,W ;If the command didn't error, but the lower 12
andlw B'00001111' ; bits of the R7 response are something besides
xorlw 0x01 ; 0x1AA, we're dealing with an unknown card, so
btfss STATUS,Z ; raise the fail flag and return to caller
bsf M_FLAGS,M_FAIL ; "
movf M_ADR0,W ; "
xorlw 0xAA ; "
btfss STATUS,Z ; "
bsf M_FLAGS,M_FAIL ; "
btfsc M_FLAGS,M_FAIL ; "
return ; "
MmcIni1 movlw 0x77 ;Send command 55 (expect R1-type response),
movwf M_CMDN ; which is a prelude to an 'app' command
clrf M_ADR3 ; "
clrf M_ADR2 ; "
clrf M_ADR1 ; "
@ -1031,17 +1073,57 @@ MmcIni1 movlw 0x41 ;Send command 1 (expect R1-type response),
bcf M_FLAGS,M_CMDLR ; "
bcf M_FLAGS,M_CMDRB ; "
call MmcCmd ; "
btfsc M_FLAGS,M_FAIL ;If this command failed, unrecognized MMC card,
return ; fail the init operation
movf M_CMDN,W ;If it returned an 0x00 status, initialization
btfsc STATUS,Z ; is finished
bra MmcIni2 ; "
decf M_CMDN,W ;If it returned an 0x01 status, initialization
btfsc STATUS,Z ; is still proceeding, so try again
movf M_CMDN,W ;If we got a status with any error bits set,
andlw B'11111110' ; treat as a command failure
btfss STATUS,Z ; "
bsf M_FLAGS,M_FAIL ; "
btfsc M_FLAGS,M_FAIL ;If this command fails, this is an unknown card
return ; so return the failure to caller
movlw 0x69 ;Send app command 41 (expect R1-type response)
movwf M_CMDN ; to initialize the card, setting the HCS
clrf M_ADR3 ; (high-capacity support) bit if we're dealing
btfsc M_FLAGS,M_CDVER ; with a V2.0+ card to let the card know that
bsf M_ADR3,6 ; we support cards bigger than 4 GB (up to 2
clrf M_ADR2 ; TB)
clrf M_ADR1 ; "
clrf M_ADR0 ; "
bcf M_FLAGS,M_CMDLR ; "
bcf M_FLAGS,M_CMDRB ; "
call MmcCmd ; "
movf M_CMDN,W ;If we got a status with any error bits set,
andlw B'11111110' ; treat as a command failure
btfss STATUS,Z ; "
bsf M_FLAGS,M_FAIL ; "
btfsc M_FLAGS,M_FAIL ;If this command fails, this is an unknown card
return ; so return the failure to caller
btfss M_CMDN,0 ;If it returned an 0x00 status, initialization
bra MmcIni2 ; is finished
DELAY 40 ;If it returned an 0x01 status, delay for 120
decfsz TEMP,F ; cycles (15 us), decrement the retry counter,
bra MmcIni1 ; and try again
decfsz TEMP2,F ; "
bra MmcIni1 ; "
bsf M_FLAGS,M_FAIL ;If it returned anything else, something is
return ; awry, fail the init operation
MmcIni2 movlw 0x50 ;Send command 16 (expect R1-type response) to
bsf M_FLAGS,M_FAIL ;If we've gone 65536 attempts and the card is
return ; still not ready, report failure to caller
MmcIni2 movlw 0x7A ;Send command 58 (expect R3-type response) to
movwf M_CMDN ; read the operating condition register (OCR)
clrf M_ADR3 ; "
clrf M_ADR2 ; "
clrf M_ADR1 ; "
clrf M_ADR0 ; "
bsf M_FLAGS,M_CMDLR ; "
bcf M_FLAGS,M_CMDRB ; "
call MmcCmd ; "
movf M_CMDN,W ;If we got a status with any error bits set,
btfss STATUS,Z ; treat as a command failure
bsf M_FLAGS,M_FAIL ; "
btfsc M_FLAGS,M_FAIL ;If this command fails, something is wrong, so
return ; return the failure to caller
bsf M_FLAGS,M_BKADR ;If the card capacity status (CCS) bit of the
btfsc M_ADR3,6 ; OCR is set, we're using block addressing, so
bra MmcIni4 ; skip ahead
MmcIni3 bcf M_FLAGS,M_BKADR ;We're dealing with byte, not block addressing
movlw 0x50 ;Send command 16 (expect R1-type response) to
movwf M_CMDN ; tell the card we want to deal in 512-byte
clrf M_ADR3 ; sectors
clrf M_ADR2 ; "
@ -1051,12 +1133,12 @@ MmcIni2 movlw 0x50 ;Send command 16 (expect R1-type response) to
bcf M_FLAGS,M_CMDLR ; "
bcf M_FLAGS,M_CMDRB ; "
call MmcCmd ; "
btfsc M_FLAGS,M_FAIL ;If this command failed, something is wrong,
return ; fail the init operation
movf M_CMDN,W ;If this command returned any response other
btfss STATUS,Z ; than 0x00, something is wrong, fail the init
bsf M_FLAGS,M_FAIL ; operation
movlw 0x7B ;Send command 59 (expect R1-type response) to
btfsc M_FLAGS,M_FAIL ;If this command failed, something is wrong,
return ; fail the init operation
MmcIni4 movlw 0x7B ;Send command 59 (expect R1-type response) to
movwf M_CMDN ; tell the card we want to make life hard on
clrf M_ADR3 ; ourselves and have our CRCs checked by the
clrf M_ADR2 ; card
@ -1066,13 +1148,16 @@ MmcIni2 movlw 0x50 ;Send command 16 (expect R1-type response) to
bcf M_FLAGS,M_CMDLR ; "
bcf M_FLAGS,M_CMDRB ; "
call MmcCmd ; "
btfsc M_FLAGS,M_FAIL ;If this command failed, something is wrong,
return ; fail the init operation
movf M_CMDN,W ;If this command returned any response other
btfss STATUS,Z ; than 0x00, something is wrong, fail the init
bsf M_FLAGS,M_FAIL ; operation
btfsc M_FLAGS,M_FAIL ;If this command failed, something is wrong,
return ; fail the init operation
bsf PORTC,RC3 ;Deassert !CS
return ;Regardless, we're done here
movf M_FLAGS,W ;Set up the card info byte of the status block
andlw B'00000111' ; "
movwf CARDINF ; "
return ;Congratulations, card is initialized!
;Convert a block address to a byte address if byte addressing is in effect.
; Sets M_FAIL if the block address is above 0x7FFFFF (and thus can't fit as a
@ -1211,7 +1296,11 @@ MmcRea4 btfss SSP1STAT,BF ;Wait until the next byte is received
btfss STATUS,Z ; "
bsf M_FLAGS,M_FAIL ; "
movlb 0 ;Return to the default bank
return
btfss M_FLAGS,M_FAIL ;If the CRC check didn't fail, return now
return ; "
call MmcStopOngoing ;If the CRC check did fail, stop any ongoing
bsf M_FLAGS,M_FAIL ; read (since the card doesn't know anything's
return ; wrong) and then return failure
;Write 512 bytes of data to MMC card from buffer pointed to by FSR0. Sets
; M_FAIL on fail. Trashes TEMP, TEMP2, and FSR0.
@ -1325,51 +1414,51 @@ MmcSto0 movlb 4 ;Switch to the bank with the SSP registers
; Trashes TEMP.
MmcCmd
bcf M_FLAGS,M_FAIL ;Assume no failure to start with
clrf M_CRC ;Start the CRC7 register out at 0
clrf TEMP ;Start the CRC7 register out at 0
movlp high LutCrc7 ;Point PCLATH to the CRC7 lookup table
movlb 4 ;Switch to the bank with the SSP registers
movf M_CMDN,W ;Clock out all six MMC buffer bytes as command,
movwf SSP1BUF ; calculating the CRC7 along the way
xorwf M_CRC,W ; "
xorwf TEMP,W ; "
callw ; "
movwf M_CRC ; "
movwf TEMP ; "
btfss SSP1STAT,BF ; "
bra $-1 ; "
movf M_ADR3,W ; "
movwf SSP1BUF ; "
xorwf M_CRC,W ; "
xorwf TEMP,W ; "
callw ; "
movwf M_CRC ; "
movwf TEMP ; "
btfss SSP1STAT,BF ; "
bra $-1 ; "
movf M_ADR2,W ; "
movwf SSP1BUF ; "
xorwf M_CRC,W ; "
xorwf TEMP,W ; "
callw ; "
movwf M_CRC ; "
movwf TEMP ; "
btfss SSP1STAT,BF ; "
bra $-1 ; "
movf M_ADR1,W ; "
movwf SSP1BUF ; "
xorwf M_CRC,W ; "
xorwf TEMP,W ; "
callw ; "
movwf M_CRC ; "
movwf TEMP ; "
btfss SSP1STAT,BF ; "
bra $-1 ; "
movf M_ADR0,W ; "
movwf SSP1BUF ; "
xorwf M_CRC,W ; "
xorwf TEMP,W ; "
callw ; "
movlp 0 ; "
movwf M_CRC ; "
bsf M_CRC,0 ; "
movwf TEMP ; "
bsf TEMP,0 ; "
btfss SSP1STAT,BF ; "
bra $-1 ; "
movf M_CRC,W ; "
movf TEMP,W ; "
movwf SSP1BUF ; "
btfss SSP1STAT,BF ; "
bra $-1 ; "
;TODO for CMD12, it is necessary to clock and throw away a stuff byte
;TODO for CMD12, it is necessary to clock and throw away a stuff byte?
movlw 8 ;Try to get status as many as eight times
movwf TEMP ; "
MmcCmd1 movlw 0xFF ;Clock a byte out of the MMC card while keeping