如下，是一个AD模块里的汇编函数，返回的是int型，请问怎么才能改成unsigned int型呢？汇编我看不懂，不知道光发这个函数大家能否看的懂？如需其他信息请告诉我，我再发上来，谢谢了顺便说下我遇到的现象吧，我用该模块采样比较小一点的电压时显示正常，但当电压超过一定值后得到的数据就会乱了，应该就是数据类型导致溢出，我在C里用IF X < 0, Y = (unsigned int) 2^15 - X但还是不行，不知道为什么，难道这个函数返回的已经错了吗？请赐教，谢谢！
;-----------------------------------------------------------------------------
; FUNCTION NAME: void AdcScan(int iResult)
;
; DESCRIPTION:
; Returns an integer value from the ADC scanning system
;
;-----------------------------------------------------------------------------
;
; ARGUMENTS:
; Latest ADC result
; A:X => Integer value returned
; A = MSB
; X = LSB
;
; RETURNS: none
;
; SIDE EFFECTS:
; REGISTERS ARE VOLATILE: THE A AND X REGISTERS MAY BE MODIFIED!
;
;-----------------------------------------------------------------------------
; A => MSB
; X => LSB
AdcScan:
_AdcScan:
RAM_PROLOGUE RAM_USE_CLASS_3
RAM_PROLOGUE RAM_USE_CLASS_4
RAM_SETPAGE_CUR >bADC_Index
RAM_SETPAGE_IDX >aiADC_Results
push X ; Push LSB
push A ; Push MSB
mov A,[bADC_Index] ; Get current index
asl A ; mult by to for correct index (2 byte ints)
mov X,A ; Setup index register for result array.
asr A
index FILTER_TABLE
jz .no_filter ; jump if no filtering required
.filter:
mov A,[X+aiADC_Results] ; previous MSB
push A ; store previous MSB
mov [bTemp+HighByte],A ; prestore MSB
inc X ; point to LSB
mov A,[X+aiADC_Results] ; previous LSB
mov [bTemp+LowByte],A ; prestore LSB
asl [bTemp+LowByte] ; mult LSB by 2
rlc [bTemp+HighByte] ; mult MSB by 2
add [bTemp+LowByte],A ; add to LSB
pop A ; restore previous MSB
adc [bTemp+HighByte],A ; add to MSB
pop A ; New MSB
add [bTemp+HighByte],A ; add new MSB
pop A ; New LSB
add [bTemp+LowByte],A ; add new LSB
adc [bTemp+HighByte],0x00 ; add carry flag
asr [bTemp+HighByte]
; dividing sum
rrc [bTemp+LowByte] ; by 4 to obtain
asr [bTemp+HighByte] ; 3/4 + 1/4
rrc [bTemp+LowByte] ; filter
mov A,[bTemp+LowByte]
mov [X+aiADC_Results],A ; write LSB to array
dec X ; point to MSB
mov A,[bTemp+HighByte]
mov [X+aiADC_Results],A ; write MSB to array
jmp .next_scan
.no_filter:
pop A ; Pop MSB of result
mov [X+aiADC_Results],A ; Write it to array
inc X ; Advance pointer to LSB
pop A ; Pop LSB of result
mov [X+aiADC_Results],A ; Write it to array
.next_scan:
mov A,[bADC_Index] ; Get current index
index MVOLTSChannelPins ; Get port/pin value of channel
push A
and A, F0h ; if port0
jz .skip_InputClear
pop A
RAM_CHANGE_PAGE_MODE( FLAG_PGMODE_11b )
lcall GlobalMux_InputClear
; Disconnect from the bus
RAM_RESTORE_NATIVE_PAGING
; Restore native paging
push A
.skip_InputClear:
pop A
inc [bADC_Index] ; Advance to next value
cmp [bADC_Index],(CMX_MVOLTS_IN_CHAN_COUNT) ; Check to see if we have if index should be reset.
jc .SetRefMux
mov [bADC_Index],0x00 ; Reset index back to zero
// Set next reference setting
.SetRefMux:
mov X,>REF_TABLE ; Get MSB of REF_TABLE ( Swap Later )
mov A,<REF_TABLE ; Put LSB of REF_TABLE in A ( Swap later )
add A,[bADC_Index] ; Add the ADC index value
swap A,X ; Move MSB to A, and LSB to X
adc A,0 ; Add the carry from the add of the REF_TABLE LSB
; and ADC_Index.
romx ; Get index value from reference table
asl A ; Shift mode 3 bits to left, to fit register alightment
asl A
asl A
and A,ARF_CR_REF ; Mask off all non-valid bits
IF (SYSTEM_LARGE_MEMORY_MODEL)
mov reg[IDX_PP],SYSTEM_STACK_PAGE ; Make sure index uses stack
ENDIF
mov X,SP
push A
mov A,reg[ARF_CR]
and A,~ARF_CR_REF ; Mask out reference setting
or A,[X] ; Set new reference setting
mov reg[ARF_CR],A
pop A
SetGain:
mov A,[bADC_Index] ; Get current channel ID
index GAIN_TABLE ; Get port/pin value of channel
RAM_CHANGE_PAGE_MODE( FLAG_PGMODE_11b )
lcall ADCBUF_SetGain
RAM_RESTORE_NATIVE_PAGING
; Restore native paging
.SetMux:
mov A,[bADC_Index] ; Get current index
index MVOLTSChannelPins ; Get port/pin value of channel
push A ; save it
and A, F0h ; if !port0
jnz .not_port0
pop A
mov reg[AMUXCFG],00h ; switch column 1 comparator input to be the column mux
RAM_CHANGE_PAGE_MODE( FLAG_PGMODE_11b )
lcall AMUX8_InputSelect
RAM_RESTORE_NATIVE_PAGING
; Restore native paging
jmp .AdcScanEnd
.not_port0:
pop A
push A
mov reg[AMUXCFG],80h ; switch column 1 comparator input to be the analog mux bus
RAM_CHANGE_PAGE_MODE( FLAG_PGMODE_11b )
lcall GlobalMux_InputSelect
RAM_RESTORE_NATIVE_PAGING
; Restore native paging
M8C_SetBank1
pop A
and A, 01h ; if pin is odd and not port0, then left mux bus, so unsplit the bus
jz .split_mux
.unsplit_mux:
and reg[DAC_CR], ~80h
.split_mux:
M8C_SetBank0
.AdcScanEnd:
RAM_EPILOGUE RAM_USE_CLASS_4
RAM_EPILOGUE RAM_USE_CLASS_3
ret
.SECTION |
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