tc.lst

Tried to make CAN logger on AT91sam7X-ek, but have no idea how to implement FATFs... -( I m just a

     76          {
     77              pTc->TC_CCR = AT91C_TC_CLKDIS;
   \                     TC_Stop:
   \   00000000   0210A0E3           MOV      R1,#+2
   \   00000004   001080E5           STR      R1,[R0, #+0]
     78          }
   \   00000008   1EFF2FE1           BX       LR               ;; return
     79          
     80          //------------------------------------------------------------------------------
     81          /// Finds the best MCK divisor given the timer frequency and MCK. The result
     82          /// is guaranteed to satisfy the following equation:
     83          /// \pre
     84          ///   (MCK / (DIV * 65536)) <= freq <= (MCK / DIV)
     85          /// \endpre
     86          /// with DIV being the highest possible value.
     87          /// \param freq  Desired timer frequency.
     88          /// \param mck  Master clock frequency.
     89          /// \param div  Divisor value.
     90          /// \param tcclks  TCCLKS field value for divisor.
     91          /// \return 1 if a proper divisor has been found; otherwise 0.
     92          //------------------------------------------------------------------------------

   \                                 In section .text, align 4, keep-with-next
     93          unsigned char TC_FindMckDivisor(
     94              unsigned int freq,
     95              unsigned int mck,
     96              unsigned int *div,
     97              unsigned int *tcclks)
     98          {
   \                     TC_FindMckDivisor:
   \   00000000   F0432DE9           PUSH     {R4-R9,LR}
   \   00000004   14D04DE2           SUB      SP,SP,#+20
   \   00000008   0040A0E1           MOV      R4,R0
   \   0000000C   0150A0E1           MOV      R5,R1
   \   00000010   0260A0E1           MOV      R6,R2
   \   00000014   0370A0E1           MOV      R7,R3
     99              const unsigned int divisors[5] = {2, 8, 32, 128,
    100          #if defined(at91sam9260) || defined(at91sam9261) || defined(at91sam9263) \
    101              || defined(at91sam9xe) || defined(at91sam9rl64) || defined(at91cap9)
    102                  BOARD_MCK / 32768};
    103          #else
    104                  1024};
   \   00000018   0D00A0E1           MOV      R0,SP
   \   0000001C   7C109FE5           LDR      R1,??TC_FindMckDivisor_0  ;; `?<Constant {2, 8, 32, 128, 1024}>`
   \   00000020   0C51B1E8           LDM      R1!,{R2,R3,R8,R12,LR}
   \   00000024   0C51A0E8           STM      R0!,{R2,R3,R8,R12,LR}
    105          #endif
    106              unsigned int index = 0;
   \   00000028   0080A0E3           MOV      R8,#+0
   \   0000002C   0D90A0E1           MOV      R9,SP
    107          
    108              // Satisfy lower bound
    109              while (freq < ((mck / divisors[index]) / 65536)) {
   \                     ??TC_FindMckDivisor_1:
   \   00000030   0500A0E1           MOV      R0,R5
   \   00000034   041099E4           LDR      R1,[R9], #+4
   \   00000038   ........           BL       __aeabi_uidivmod
   \   0000003C   200854E1           CMP      R4,R0, LSR #+16
   \   00000040   0500002A           BCS      ??TC_FindMckDivisor_2
    110          
    111                  index++;
   \   00000044   018088E2           ADD      R8,R8,#+1
    112          
    113                  // If no divisor can be found, return 0
    114                  if (index == 5) {
   \   00000048   050058E3           CMP      R8,#+5
   \   0000004C   F7FFFF1A           BNE      ??TC_FindMckDivisor_1
    115          
    116                      return 0;
   \   00000050   0000A0E3           MOV      R0,#+0
   \   00000054   0E0000EA           B        ??TC_FindMckDivisor_3
    117                  }
    118              }
    119          
    120              // Try to maximise DIV while satisfying upper bound
    121              while (index < 4) {
    122          
    123                  if (freq > (mck / divisors[index + 1])) {
    124          
    125                      break;
    126                  }
    127                  index++;
   \                     ??TC_FindMckDivisor_4:
   \   00000058   018088E2           ADD      R8,R8,#+1
   \                     ??TC_FindMckDivisor_2:
   \   0000005C   040058E3           CMP      R8,#+4
   \   00000060   0500002A           BCS      ??TC_FindMckDivisor_5
   \   00000064   0500A0E1           MOV      R0,R5
   \   00000068   08118DE0           ADD      R1,SP,R8, LSL #+2
   \   0000006C   041091E5           LDR      R1,[R1, #+4]
   \   00000070   ........           BL       __aeabi_uidivmod
   \   00000074   040050E1           CMP      R0,R4
   \   00000078   F6FFFF2A           BCS      ??TC_FindMckDivisor_4
    128              }
    129          
    130              // Store results
    131              if (div) {
   \                     ??TC_FindMckDivisor_5:
   \   0000007C   000056E3           CMP      R6,#+0
    132          
    133                  *div = divisors[index];
   \   00000080   08019D17           LDRNE    R0,[SP, +R8, LSL #+2]
   \   00000084   00008615           STRNE    R0,[R6, #+0]
    134              }
    135              if (tcclks) {
   \   00000088   000057E3           CMP      R7,#+0
    136          
    137                  *tcclks = index;
   \   0000008C   00808715           STRNE    R8,[R7, #+0]
    138              }
    139          
    140              return 1;
   \   00000090   0100A0E3           MOV      R0,#+1
   \                     ??TC_FindMckDivisor_3:
   \   00000094   14D08DE2           ADD      SP,SP,#+20       ;; stack cleaning
   \   00000098   F043BDE8           POP      {R4-R9,LR}
   \   0000009C   1EFF2FE1           BX       LR               ;; return
   \                     ??TC_FindMckDivisor_0:
   \   000000A0   ........           DC32     `?<Constant {2, 8, 32, 128, 1024}>`
    141          }

   \                                 In section .rodata, align 4
   \                     `?<Constant {2, 8, 32, 128, 1024}>`:
   \   00000000   020000000800       DC32 2, 8, 32, 128, 1024
   \              000020000000
   \              800000000004
   \              0000        
    142          

   Maximum stack usage in bytes:

     Function          .cstack
     --------          -------
     TC_Configure           0
     TC_FindMckDivisor      0
     TC_Start               0
     TC_Stop                0


   Section sizes:

     Function/Label                    Bytes
     --------------                    -----
     TC_Configure                        28
     TC_Start                            12
     TC_Stop                             12
     TC_FindMckDivisor                  164
     ?<Constant {2, 8, 32, 128, 1024}>   20

 
  20 bytes in section .rodata
 216 bytes in section .text
 
 216 bytes of CODE  memory
  20 bytes of CONST memory

Errors: none
Warnings: none