20220611
This commit is contained in:
lampmerchant
parent
cce0da8f02
commit
9bbf602c8a
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@ -88,12 +88,10 @@ IWMCNT0 equ 0 ; "
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;M_FLAGS:
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M_FAIL equ 7 ;Set when there's been a failure on the MMC interface
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M_CMDLR equ 6 ;Set when R3 or R7 is expected (5 bytes), not R1
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M_CMDRB equ 5 ;Set when an R1b is expected (busy signal after reply)
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M_RDCMD equ 4 ;Set when state machine should do a read command
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M_ONGWR equ 3 ;Set when state machine shouldn't stop tran on a write
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M_BKADR equ 2 ;Set when block (rather than byte) addressing is in use
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M_CDVER equ 1 ;Set when dealing with a V2.0+ card, clear for 1.0
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M_RDCMD equ 6 ;Set when state machine should do a read command
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M_ONGWR equ 5 ;Set when state machine shouldn't stop tran on a write
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M_BKADR equ 4 ;Set when block (rather than byte) addressing is in use
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M_CDVER equ 3 ;Set when dealing with a V2.0+ card, clear for 1.0
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;;; Variable Storage ;;;
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@ -693,16 +691,13 @@ SysInit
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SysIni0 bsf CS_PORT,CS_PIN ;Deassert !CS
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movlw 0x51 ;Set up a read command for the card (R1-type
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movwf M_CMDN ; response)
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bcf M_FLAGS,M_CMDLR ; "
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bcf M_FLAGS,M_CMDRB ; "
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clrf M_ADR3 ;Point the card address to the master boot
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clrf M_ADR2 ; record
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clrf M_ADR1 ; "
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clrf M_ADR0 ; "
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bcf CS_PORT,CS_PIN ;Assert !CS
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call MmcCmd ;Send the read command
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movf M_CMDN,W ;Treat any error flag as a failed command
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andlw B'11111110' ; "
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andlw B'11111110' ;Treat any error flag as a failed command
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btfss STATUS,Z ; "
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bsf M_FLAGS,M_FAIL ; "
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movlw 10 ;If the operation failed, give up and pass a
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@ -762,16 +757,13 @@ SysIni3 bsf CS_PORT,CS_PIN ;Deassert !CS
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bra SysIni4 ; "
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movlw 0x51 ;Set up a read command for the card (R1-type
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movwf M_CMDN ; response)
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bcf M_FLAGS,M_CMDLR ; "
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bcf M_FLAGS,M_CMDRB ; "
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clrf M_ADR3 ;The rest of the address is all zeroes
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clrf M_ADR2 ; "
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clrf M_ADR1 ; "
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call MmcConvAddr ;Convert address to bytes if necessary
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bcf CS_PORT,CS_PIN ;Assert !CS
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call MmcCmd ;Send the read command
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movf M_CMDN,W ;Treat any error flag as a failed command
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andlw B'11111110' ; "
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andlw B'11111110' ;Treat any error flag as a failed command
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btfss STATUS,Z ; "
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bsf M_FLAGS,M_FAIL ; "
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movlw 14 ;If the operation failed, give up and pass a
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@ -1254,13 +1246,10 @@ CmdWrite
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btfsc M_FLAGS,M_ONGWR ;If we're starting a new write even though a
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bra CmdWri6 ; multiblock write is ongoing, handle it
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movlw 0x59 ;Set up a multiblock write command for the card
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movwf M_CMDN ; (R1-type reply)
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bcf M_FLAGS,M_CMDLR ; "
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bcf M_FLAGS,M_CMDRB ; "
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movwf M_CMDN ; (R1-type response)
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bcf CS_PORT,CS_PIN ;Assert !CS
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call MmcCmd ;Send the command
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movf M_CMDN,W ;Treat any error flag as a failed command
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andlw B'11111110' ; "
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andlw B'11111110' ;Treat any error flag as a failed command
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btfss STATUS,Z ; "
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bsf M_FLAGS,M_FAIL ; "
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btfsc M_FLAGS,M_FAIL ;If there was any failure, respond with a
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@ -1635,15 +1624,12 @@ MmcIni1 movlw 0xFF ; "
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clrf M_ADR2 ; "
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clrf M_ADR1 ; "
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clrf M_ADR0 ; "
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bcf M_FLAGS,M_CMDLR ; "
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bcf M_FLAGS,M_CMDRB ; "
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call MmcCmd ; "
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btfsc M_FLAGS,M_FAIL ;If this command failed, unrecognized or
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retlw 1 ; missing MMC card, fail the init operation
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movf M_CMDN,W ;If this command returned any response other
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xorlw 0x01 ; than 0x01 ('in idle state'), unrecognized MMC
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btfss STATUS,Z ; card, fail the init operation
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retlw 2 ; "
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xorlw 0x01 ;If this command returned any response other
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btfss STATUS,Z ; than 0x01 ('in idle state'), unrecognized MMC
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retlw 2 ; card, fail the init operation
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bsf M_FLAGS,M_CDVER ;Assume version 2.0+ to begin with
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clrf X2 ;Set retry counter to 0 (65536) for later use
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clrf X3 ; "
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@ -1655,16 +1641,14 @@ MmcIni1 movlw 0xFF ; "
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movwf M_ADR1 ; "
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movlw 0xAA ; "
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movwf M_ADR0 ; "
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bsf M_FLAGS,M_CMDLR ; "
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bcf M_FLAGS,M_CMDRB ; "
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call MmcCmd ; "
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movf M_CMDN,W ;If the command set any error flags or there
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andlw B'11111110' ; was no response, switch assumptions and guess
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btfsc STATUS,Z ; that we're dealing with a Version 1 card and
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btfsc M_FLAGS,M_FAIL ; jump ahead to initialize it
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bcf M_FLAGS,M_CDVER ; "
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andlw B'11111110' ;If the command set any error flags or there
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btfsc STATUS,Z ; was no response, switch assumptions and guess
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btfsc M_FLAGS,M_FAIL ; that we're dealing with a Version 1 card and
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bcf M_FLAGS,M_CDVER ; jump ahead to initialize it
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btfss M_FLAGS,M_CDVER ; "
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bra MmcIni2 ; "
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call MmcExtResponse ;Command didn't error, so get the R7 response
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movf M_ADR1,W ;If the command didn't error, but the lower 12
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andlw B'00001111' ; bits of the R7 response are something besides
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xorlw 0x01 ; 0x1AA, we're dealing with an unknown card, so
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@ -1680,12 +1664,9 @@ MmcIni2 movlw 0x77 ;Send command 55 (expect R1-type response),
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clrf M_ADR2 ; "
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clrf M_ADR1 ; "
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clrf M_ADR0 ; "
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bcf M_FLAGS,M_CMDLR ; "
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bcf M_FLAGS,M_CMDRB ; "
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call MmcCmd ; "
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movf M_CMDN,W ;If we got a status with any error bits set,
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andlw B'11111110' ; treat as a command failure
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btfss STATUS,Z ; "
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andlw B'11111110' ;If we got a status with any error bits set,
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btfss STATUS,Z ; treat as a command failure
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bsf M_FLAGS,M_FAIL ; "
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btfsc M_FLAGS,M_FAIL ;If this command fails, this is an unknown card
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retlw 4 ; so return the failure to caller
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@ -1697,17 +1678,14 @@ MmcIni2 movlw 0x77 ;Send command 55 (expect R1-type response),
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clrf M_ADR2 ; TB)
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clrf M_ADR1 ; "
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clrf M_ADR0 ; "
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bcf M_FLAGS,M_CMDLR ; "
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bcf M_FLAGS,M_CMDRB ; "
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call MmcCmd ; "
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movf M_CMDN,W ;If we got a status with any error bits set,
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andlw B'11111110' ; treat as a command failure
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btfss STATUS,Z ; "
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btfsc STATUS,Z ;If it returned an 0x00 status, initialization
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bra MmcIni3 ; is finished
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andlw B'11111110' ;If we got a status with any error bits set,
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btfss STATUS,Z ; treat as a command failure
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bsf M_FLAGS,M_FAIL ; "
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btfsc M_FLAGS,M_FAIL ;If this command fails, this is an unknown card
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retlw 5 ; so return the failure to caller
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btfss M_CMDN,0 ;If it returned an 0x00 status, initialization
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bra MmcIni3 ; is finished
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DELAY 40 ;If it returned an 0x01 status, delay for 120
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decfsz X2,F ; cycles (15 us), decrement the retry counter,
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bra MmcIni2 ; and try again
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@ -1720,14 +1698,12 @@ MmcIni3 movlw 0x7A ;Send command 58 (expect R3-type response) to
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clrf M_ADR2 ; "
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clrf M_ADR1 ; "
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clrf M_ADR0 ; "
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bsf M_FLAGS,M_CMDLR ; "
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bcf M_FLAGS,M_CMDRB ; "
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call MmcCmd ; "
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movf M_CMDN,W ;If we got a status with any error bits set,
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btfss STATUS,Z ; treat as a command failure
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bsf M_FLAGS,M_FAIL ; "
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btfss STATUS,Z ;If we got a status with any error bits set,
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bsf M_FLAGS,M_FAIL ; treat as a command failure
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btfsc M_FLAGS,M_FAIL ;If this command fails, something is wrong, so
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retlw 7 ; return the failure to caller
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call MmcExtResponse ;Command didn't fail, so get R3 response
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bsf M_FLAGS,M_BKADR ;If the card capacity status (CCS) bit of the
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btfsc M_ADR3,6 ; OCR is set, we're using block addressing, so
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bra MmcIni4 ; skip ahead
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@ -1739,12 +1715,9 @@ MmcIni3 movlw 0x7A ;Send command 58 (expect R3-type response) to
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movlw 0x02 ; "
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movwf M_ADR1 ; "
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clrf M_ADR0 ; "
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bcf M_FLAGS,M_CMDLR ; "
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bcf M_FLAGS,M_CMDRB ; "
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call MmcCmd ; "
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movf M_CMDN,W ;If this command returned any response other
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btfss STATUS,Z ; than 0x00, something is wrong, fail the init
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bsf M_FLAGS,M_FAIL ; operation
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btfss STATUS,Z ;If this command returned any nonzero response,
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bsf M_FLAGS,M_FAIL ; something is wrong, fail the init operation
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btfsc M_FLAGS,M_FAIL ;If this command failed, something is wrong,
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retlw 8 ; fail the init operation
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MmcIni4 movlw 0x7B ;Send command 59 (expect R1-type response) to
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@ -1754,12 +1727,9 @@ MmcIni4 movlw 0x7B ;Send command 59 (expect R1-type response) to
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clrf M_ADR1 ; "
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movlw 0x01 ; "
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movwf M_ADR0 ; "
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bcf M_FLAGS,M_CMDLR ; "
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bcf M_FLAGS,M_CMDRB ; "
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call MmcCmd ; "
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movf M_CMDN,W ;If this command returned any response other
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btfss STATUS,Z ; than 0x00, something is wrong, fail the init
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bsf M_FLAGS,M_FAIL ; operation
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btfss STATUS,Z ;If this command returned any nonzero response,
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bsf M_FLAGS,M_FAIL ; something is wrong, fail the init operation
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btfsc M_FLAGS,M_FAIL ;If this command failed, something is wrong,
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retlw 9 ; fail the init operation
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retlw 0 ;Congratulations, card is initialized!
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@ -1809,9 +1779,23 @@ MmcIncAddr
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; fail. Trashes X0 and X1.
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MmcCmd
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bcf M_FLAGS,M_FAIL ;Assume no failure to start with
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clrf X0 ;Start the CRC7 register out at 0
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movlp high LutCrc7 ;Point PCLATH to the CRC7 lookup table
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movlb 4 ;Switch to the bank with the SSP registers
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movlw 8 ;Make sure the MMC card is ready for a command
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movwf X0 ; by clocking up to 8 bytes to get an 0xFF
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MmcCmd0 movlw 0xFF ;Clock a byte out of the MMC card while keeping
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movwf SSP1BUF ; MOSI high
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btfss SSP1STAT,BF ; "
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bra $-1 ; "
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xorwf SSP1BUF,W ;If we got an 0xFF back from the MMC card, it
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btfsc STATUS,Z ; is ready to accept a command
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bra MmcCmd1 ; "
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decfsz X0,F ;Decrement the attempt counter until we've
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bra MmcCmd0 ; tried eight times; if card hasn't responded
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bsf M_FLAGS,M_FAIL ; 0xFF by the eighth attempt, signal failure
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movlb 0 ;Restore BSR to 0 and return
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return ; "
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MmcCmd1 clrf X0 ;Start the CRC7 register out at 0
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movlp high LutCrc7 ;Point PCLATH to the CRC7 lookup table
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movf M_CMDN,W ;Clock out all six MMC buffer bytes as command,
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movwf SSP1BUF ; calculating the CRC7 along the way
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xorwf X0,W ; "
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@ -1856,50 +1840,50 @@ MmcCmd
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;TODO for CMD12, it is necessary to clock and throw away a stuff byte?
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movlw 8 ;Try to get status as many as eight times
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movwf X0 ; "
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MmcCmd1 movlw 0xFF ;Clock a byte out of the MMC card while keeping
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MmcCmd2 movlw 0xFF ;Clock a byte out of the MMC card while keeping
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movwf SSP1BUF ; MOSI high
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btfss SSP1STAT,BF ; "
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bra $-1 ; "
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incf SSP1BUF,W ;If we read back anything but 0xFF, skip ahead
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btfss STATUS,Z ; "
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bra MmcCmd2 ; "
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incf SSP1BUF,W ;Read the received byte; if it's anything but
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btfss STATUS,Z ; 0xFF, that's a result so skip ahead
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bra MmcCmd3 ; "
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decfsz X0,F ;Decrement the attempt counter until we've
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bra MmcCmd1 ; tried eight times; if we haven't gotten a
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bsf M_FLAGS,M_FAIL ; reply by the eighth attempt, signal failure
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movlb 0 ; and return
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bra MmcCmd2 ; tried eight times; if card hasn't responded
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bsf M_FLAGS,M_FAIL ; by the eighth attempt, signal failure
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MmcCmd3 decf WREG,W ;Decrement W so it reflects the last byte read
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movlb 0 ;Restore BSR to 0 and return
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return ; "
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MmcCmd2 decf WREG,W ;Store the byte we received as R1-type status
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movwf M_CMDN ; in the buffer
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btfss M_FLAGS,M_CMDLR ;If we aren't expecting a long (R3/R7-type)
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bra MmcCmd3 ; reply, we're done
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movlw 0xFF ;Clock first extended reply byte out of the
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;Read the extended response of a command returning an R3 or R7 type response
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; into M_ADR3-0.
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MmcExtResponse
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movlb 4 ;Switch to the bank with the SSP registers
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movlw 0xFF ;Clock first extended response byte out of the
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movwf SSP1BUF ; MMC card while keeping MOSI high and store it
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btfss SSP1STAT,BF ; in the buffer
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bra $-1 ; "
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movf SSP1BUF,W ; "
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movwf M_ADR3 ; "
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movlw 0xFF ;Clock second extended reply byte out of the
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movlw 0xFF ;Clock second extended response byte out of the
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movwf SSP1BUF ; MMC card while keeping MOSI high and store it
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btfss SSP1STAT,BF ; in the buffer
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bra $-1 ; "
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movf SSP1BUF,W ; "
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movwf M_ADR2 ; "
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movlw 0xFF ;Clock third extended reply byte out of the
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movlw 0xFF ;Clock third extended response byte out of the
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movwf SSP1BUF ; MMC card while keeping MOSI high and store it
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btfss SSP1STAT,BF ; in the buffer
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bra $-1 ; "
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movf SSP1BUF,W ; "
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movwf M_ADR1 ; "
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movlw 0xFF ;Clock fourth extended reply byte out of the
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movlw 0xFF ;Clock fourth extended response byte out of the
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movwf SSP1BUF ; MMC card while keeping MOSI high and store it
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btfss SSP1STAT,BF ; in the buffer
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bra $-1 ; "
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movf SSP1BUF,W ; "
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movwf M_ADR0 ; "
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MmcCmd3 btfsc M_FLAGS,M_CMDRB ;If we're expecting an R1b reply, wait for the
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call MmcWaitBusy ; card not to be busy anymore before returning
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movlb 0 ;Restore BSR to 0
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return
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movlb 0 ;Restore BSR to 0 and return
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return ; "
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;Waits for the card not to be busy anymore. Sets M_FAIL on fail. Trashes X0
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; and X1. Expects BSR to be 4 and does not set or reset this.
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@ -2124,25 +2108,29 @@ MSSWaitCmd
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movlb 0 ;Assert !CS
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bcf CS_PORT,CS_PIN ; "
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movlb 4 ; "
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movlw 0xFF ;Clock first ready-for-command? byte out of the
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movwf SSP1BUF ; card
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movlb 0 ;Clear the SSP interrupt flag because it's in
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bcf PIR1,SSP1IF ; use now
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retlw MSSRdCmd1 - MSS ;Transition to the next read command state
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MSSRdCmd1
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incf SSP1BUF,W ;If card clocked back anything but 0xFF, it's
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btfsc STATUS,Z ; not ready for a command, so clock out another
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bra $+6 ; byte and try again
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movlw 0xFF ; "
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movwf SSP1BUF ; "
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movlb 0 ; "
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bcf PIR1,SSP1IF ; "
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retlw MSSRdCmd1 - MSS ; "
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movlw 0x51 ;Clock out the command byte for a read
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movwf SSP1BUF ; "
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movlw 0xE8 ;Set up the CRC register with the CRC7 of the
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movwf M_CRCL ; read command byte
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movlb 0 ;Clear the SSP interrupt flag because it's in
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bcf PIR1,SSP1IF ; use now
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retlw MSSRdCmd1 - MSS ;Transition to the next read command state
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MSSRdCmd1
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movf M_ADR3,W ;Clock out the high byte of the address
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movwf SSP1BUF ; "
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movlp high LutCrc7 ;Update the CRC for the command
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xorwf M_CRCL,W ; "
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callw ; "
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movwf M_CRCL ; "
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movlb 0 ;Clear the SSP interrupt flag because it's in
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bcf PIR1,SSP1IF ; use now
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retlw MSSRdCmd2 - MSS ;Transition to the next read command state
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MSSRdCmd2
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movf M_ADR2,W ;Clock out the next byte of the address
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movf M_ADR3,W ;Clock out the high byte of the address
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movwf SSP1BUF ; "
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movlp high LutCrc7 ;Update the CRC for the command
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xorwf M_CRCL,W ; "
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@ -2152,7 +2140,7 @@ MSSRdCmd2
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bcf PIR1,SSP1IF ; use now
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retlw MSSRdCmd3 - MSS ;Transition to the next read command state
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MSSRdCmd3
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movf M_ADR1,W ;Clock out the next byte of the address
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movf M_ADR2,W ;Clock out the next byte of the address
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movwf SSP1BUF ; "
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movlp high LutCrc7 ;Update the CRC for the command
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xorwf M_CRCL,W ; "
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@ -2162,7 +2150,7 @@ MSSRdCmd3
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bcf PIR1,SSP1IF ; use now
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retlw MSSRdCmd4 - MSS ;Transition to the next read command state
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MSSRdCmd4
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movf M_ADR0,W ;Clock out the low byte of the address
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movf M_ADR1,W ;Clock out the next byte of the address
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movwf SSP1BUF ; "
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movlp high LutCrc7 ;Update the CRC for the command
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xorwf M_CRCL,W ; "
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@ -2172,26 +2160,36 @@ MSSRdCmd4
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bcf PIR1,SSP1IF ; use now
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retlw MSSRdCmd5 - MSS ;Transition to the next read command state
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MSSRdCmd5
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movf M_ADR0,W ;Clock out the low byte of the address
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movwf SSP1BUF ; "
|
||||
movlp high LutCrc7 ;Update the CRC for the command
|
||||
xorwf M_CRCL,W ; "
|
||||
callw ; "
|
||||
movwf M_CRCL ; "
|
||||
movlb 0 ;Clear the SSP interrupt flag because it's in
|
||||
bcf PIR1,SSP1IF ; use now
|
||||
retlw MSSRdCmd6 - MSS ;Transition to the next read command state
|
||||
MSSRdCmd6
|
||||
movf M_CRCL,W ;Clock out the CRC for the command
|
||||
movwf SSP1BUF ; "
|
||||
bcf M_FLAGS,M_RDCMD ;Read command complete, M_ADR* are free
|
||||
movlb 0 ;Clear the SSP interrupt flag because it's in
|
||||
bcf PIR1,SSP1IF ; use now
|
||||
retlw MSSRdCmd6 - MSS ;Transition to the next read command state
|
||||
MSSRdCmd6
|
||||
retlw MSSRdCmd7 - MSS ;Transition to the next read command state
|
||||
MSSRdCmd7
|
||||
movlw 0xFF ;Clock first is-still-busy? byte out of the
|
||||
movwf SSP1BUF ; card
|
||||
movlb 0 ;Clear the SSP interrupt flag because it's in
|
||||
bcf PIR1,SSP1IF ; use now
|
||||
retlw MSSRdCmd7 - MSS ; "
|
||||
MSSRdCmd7
|
||||
retlw MSSRdCmd8 - MSS ; "
|
||||
MSSRdCmd8
|
||||
btfss SSP1BUF,7 ;If MSB is set, this isn't an R1 response byte,
|
||||
bra $+6 ; so clock out another byte and try again
|
||||
movlw 0xFF ; "
|
||||
movwf SSP1BUF ; "
|
||||
movlb 0 ; "
|
||||
bcf PIR1,SSP1IF ; "
|
||||
retlw MSSRdCmd7 - MSS ; "
|
||||
retlw MSSRdCmd8 - MSS ; "
|
||||
movf SSP1BUF,W ;If MSB is clear but an error bit is set, the
|
||||
andlw B'11111110' ; command was not processed, so go back to the
|
||||
btfsc STATUS,Z ; WaitCmd state after deasserting !CS
|
||||
|
|
|
|||
Loading…
Reference in New Issue