avr/mmc-old.asm

   1 ; ----------------- MMC/SD routines ------------------
   2
   3 mmcByteNoSend:
   4         ldi temp,0xff
   5 mmcByte:
   6
   7 .if MMC_DEBUG
   8         printstring "MMC: <--"
   9         rcall printhex
  10 .endif
  11
  12         out SPDR,temp
  13 mmcWrByteW:
  14         in temp,SPSR
  15         sbrs temp,7
  16          rjmp mmcWrByteW
  17         in temp,SPDR
  18
  19 .if MMC_DEBUG
  20         printstring ", -->"
  21         rcall printhex
  22         printnewline
  23 .endif
  24         ret
  25
  26
  27 ;Wait till the mmc answers with the response in temp2, or till a timeout happens.
  28 mmcWaitResp:
  29         ldiw z,0
  30 mmcWaitResploop:
  31         rcall mmcByteNoSend
  32         cpi temp,0xff
  33         brne mmcWaitResploopEnd
  34         adiw zl,1
  35         cpi zh,255
  36         breq mmcWaitErr
  37         rjmp mmcWaitResploop
  38 mmcWaitResploopEnd:
  39         ret
  40
  41
  42 mmcWaitErr:
  43         mov temp,temp2
  44         rcall printhex
  45         printstring ": Error: MMC resp timeout!"
  46         printnewline
  47         rjmp resetAVR
  48
  49 mmcInit:
  50         ldi temp,0x53
  51         out SPCR,temp
  52
  53         ;Init start: send 80 clocks with cs disabled
  54         sbi P_MMC_CS,mmc_cs
  55
  56 ;       ldi temp2,20
  57         ldi temp2,10     ; exactly 80 clocks
  58 mmcInitLoop:
  59         mov temp,temp2
  60         rcall mmcByte
  61         dec temp2
  62         brne mmcInitLoop
  63
  64         cbi P_MMC_CS,mmc_cs
  65         rcall mmcByteNoSend
  66         rcall mmcByteNoSend
  67         rcall mmcByteNoSend
  68         rcall mmcByteNoSend
  69         rcall mmcByteNoSend
  70         rcall mmcByteNoSend
  71         sbi P_MMC_CS,mmc_cs
  72         rcall mmcByteNoSend
  73         rcall mmcByteNoSend
  74         rcall mmcByteNoSend
  75         rcall mmcByteNoSend
  76
  77         ;Send init command
  78         cbi P_MMC_CS,mmc_cs
  79         ldi temp,0xff   ;dummy
  80         rcall mmcByte
  81         ldi temp,0xff   ;dummy
  82         rcall mmcByte
  83         ldi temp,0x40   ;cmd
  84         rcall mmcByte
  85         ldi temp,0      ;pxh
  86         rcall mmcByte
  87         ldi temp,0      ;pxl
  88         rcall mmcByte
  89         ldi temp,0      ;pyh
  90         rcall mmcByte
  91         ldi temp,0      ;pyl
  92         rcall mmcByte
  93         ldi temp,0x95   ;crc
  94         rcall mmcByte
  95         ldi temp,0xff   ;return byte
  96         rcall mmcByte
  97
  98         ldi temp2,0                     ;Error Code 0
  99         rcall mmcWaitResp               ;Test on CMD0 is OK
 100
 101         sbi P_MMC_CS,mmc_cs             ;disable /CS
 102         rcall mmcByteNoSend
 103
 104
 105 ;Read OCR till card is ready
 106         ldi temp2,100                   ;repeat counter
 107 mmcInitOcrLoop:
 108         push temp2
 109
 110         cbi P_MMC_CS,mmc_cs             ;enable /CS
 111         ldi temp,0xff   ;dummy
 112         rcall mmcByte
 113         ldi temp,0x41   ;cmd
 114         rcall mmcByte
 115         ldi temp,0      ;pxh
 116         rcall mmcByte
 117         ldi temp,0      ;pxl
 118         rcall mmcByte
 119         ldi temp,0      ;pyh
 120         rcall mmcByte
 121         ldi temp,0      ;pyl
 122         rcall mmcByte
 123 ;       ldi temp,0x95                   ;crc
 124         ldi temp,0x01                   ;crc
 125         rcall mmcByte
 126         rcall mmcByteNoSend
 127
 128         ldi temp2,1
 129         rcall mmcWaitResp               ;wait until mmc-card send a byte <> 0xFF
 130                                         ;the first answer must be 0x01 (Idle-Mode)
 131         cpi temp,0
 132         breq mmcInitOcrLoopDone         ;second answer is 0x00 (Idle-Mode leave) CMD1 is OK
 133
 134         sbi P_MMC_CS,mmc_cs             ;disable /CS
 135
 136         rcall mmcByteNoSend
 137
 138         ldi     temp,10
 139         rcall   delay_ms
 140
 141         pop temp2
 142         dec temp2
 143         brne mmcInitOcrLoop             ;repeat
 144
 145         ldi temp2,4
 146         rjmp mmcWaitErr
 147
 148 mmcInitOcrLoopDone:
 149         pop temp2
 150         sbi P_MMC_CS,mmc_cs             ;disable /CS
 151         rcall mmcByteNoSend
 152
 153         out SPCR,_0
 154         ret
 155
 156
 157 ;Call this with yh:yl:xh:xl = sector number
 158 ;
 159 mmcReadSect:
 160         ldi temp,0x50
 161         out SPCR,temp
 162
 163         cbi P_MMC_CS,mmc_cs
 164         rcall mmcByteNoSend
 165         ldi temp,0x51   ;cmd (read sector)
 166         rcall mmcByte
 167         lsl     xl                      ;convert to byte address (*512)
 168         rol     xh
 169         rol     yl
 170         mov     temp,yl
 171         rcall mmcByte
 172         mov temp,xh ;pxl
 173         rcall mmcByte
 174         mov temp,xl ;pyh
 175         rcall mmcByte
 176         ldi temp,0  ;pyl
 177         rcall mmcByte
 178         ldi temp,0x95   ;crc
 179         rcall mmcByte
 180         ldi temp,0xff   ;return byte
 181         rcall mmcByte
 182
 183         ;resp
 184         ldi temp2,2
 185         rcall mmcWaitResp
 186
 187         ;data token
 188         ldi temp2,3
 189         rcall mmcWaitResp
 190
 191         ;Read sector to AVR RAM
 192         ldiw    z,hostbuf
 193 mmcreadloop:
 194         rcall mmcByteNoSend
 195         st z+,temp
 196         cpi zl,low(hostbuf+512)
 197         brne mmcreadloop
 198         cpi zh,high(hostbuf+512)
 199         brne mmcreadloop
 200
 201         ;CRC
 202         rcall mmcByteNoSend
 203         rcall mmcByteNoSend
 204
 205         sbi P_MMC_CS,mmc_cs
 206         rcall mmcByteNoSend
 207
 208         out SPCR,_0
 209         ret
 210
 211
 212 ;Call this with yh:yl:xh:xl = sector number
 213 ;
 214 mmcWriteSect:
 215         ldi temp,0x50
 216         out SPCR,temp
 217
 218         cbi P_MMC_CS,mmc_cs
 219         rcall mmcByteNoSend
 220
 221         ldi temp,0x58   ;cmd (write sector)
 222         rcall mmcByte
 223         lsl     xl                      ;convert to byte address (*512)
 224         rol     xh
 225         rol     yl
 226         mov     temp,yl
 227         rcall mmcByte
 228         mov temp,xh ;pxl
 229         rcall mmcByte
 230         mov temp,xl ;pyh
 231         rcall mmcByte
 232         ldi temp,0  ;pyl
 233         rcall mmcByte
 234         ldi temp,0x95   ;crc
 235         rcall mmcByte
 236         ldi temp,0xff   ;return byte
 237         rcall mmcByte
 238
 239         ;resp
 240         ldi temp2,1
 241         rcall mmcWaitResp
 242
 243         ;Send data token
 244         ldi temp,0xfe
 245         rcall mmcByte
 246
 247         ;Write sector from AVR RAM
 248         ldiw    z,hostbuf
 249 mmcwriteloop:
 250         ld temp,z+
 251         rcall mmcByte
 252         cpi zl,low(hostbuf+512)
 253         brne mmcwriteloop
 254         cpi zh,high(hostbuf+512)
 255         brne mmcwriteloop
 256
 257         ;CRC
 258         rcall mmcByteNoSend
 259         rcall mmcByteNoSend
 260
 261         ;Status. Ignored for now.
 262         rcall mmcByteNoSend
 263
 264 ;Wait till the mmc has written everything
 265 mmcwaitwritten:
 266         rcall mmcByteNoSend
 267         cpi temp,0xff
 268         brne mmcwaitwritten
 269
 270         sbi P_MMC_CS,mmc_cs
 271         rcall mmcByteNoSend
 272
 273         out SPCR,_0
 274         ret
 275
 276
 277 ;Set up wdt to time out after 1 sec.
 278 resetAVR:
 279         lds     temp,txcount    ;Wait, till tx buffer is empty
 280         tst     temp
 281         brne    resetAVR
 282
 283         cli
 284         ldi temp,(1<<WDCE)
 285         outm8 WDTCSR,temp
 286         ldi temp,(1<<WDCE) | (1<<WDE) | (110<<WDP0)
 287         outm8 WDTCSR,temp
 288 resetwait:
 289         rjmp resetwait
 290
 291