slavuart.lst

aduc842原程序代码 ad公司芯片应用笔记

SLAVUART                                                                                                      PAGE 1

                       1    ;====================================================================
                       2    ;
                       3    ; Author        : ADI - Apps
                       4    ;
                       5    ; Date          : October 2003
                       6    ;
                       7    ; File          : SLAVuart.asm
                       8    ;
                       9    ; Hardware      : ADuC842
                      10    ;
                      11    ; Description   : This slave program transmits the numbers 11-20 in 
                      12    ;                 binary form continuously down the SPI serial port 
                      13    ;                 after receiving a clock signal. 
                      14    ;                 
                      15    ;                 After the transmission of each byte the incoming 
                      16    ;                 byte is saved in order at an internal RAM address 
                      17    ;                 between #40h and #50h.
                      18    ;
                      19    ;                 This program can be used with the master program 
                      20    ;                 MASTuart.asm (which generates a clock signal for 
                      21    ;                 the slave) 
                      22    ;
                      23    ;                 After the 16 input bytes have been stored in memory
                      24    ;                 the values in memory are outputted up the UART to 
                      25    ;                 the PC where they can be viewed on screen by a 
                      26    ;                 program such as Hyperterminal. After each 
                      27    ;                 transmission up the UART the program is delayed for
                      28    ;                 1s before returning from the interrupt. It then 
                      29    ;                 waits for the next data byte from the SPI port
                      30    ;                 which will arrive about 4s later if used with the 
                      31    ;                 Master program (MASTuart.asm).
                      32    ;
                      33    ;                 The Slave program (SLAVuart.asm) should be started 
                      34    ;                 after the master program (MASTuart.asm) but within
                      35    ;                 the time delay of 2s in order that the slave 
                      36    ;                 program is synchronised by the first outputted 
                      37    ;                 clock of the master.
                      38    ;
                      39    ;                 The clock is inputted at sclock (pin 26)
                      40    ;                 The data is outputted at MISO (pin 14)
                      41    ;                 The data is inputted at sdata/MOSI (pin 27)   
                      42    ;====================================================================
                      43    ;       
                      44    $MOD842                                  ;Use 8052 predefined Symbols
                      45    
  00B4                46    LED     EQU     P3.4
  0000                47    FLAG    BIT     00H
                      48    
                      49    ;____________________________________________________________________
                      50                                                      ; BEGINNING OF CODE
----                  51    CSEG
0000                  52    ORG 0000H
                      53    
0000 020060           54            JMP MAIN
                      55    ;____________________________________________________________________
                      56                                                  ; SPI INTERRUPT ROUTINE
003B                  57    ORG 003BH
003B C200             58            CLR     FLAG          ; Clear flag to leave LOOP2
SLAVUART                                                                                                      PAGE 2

                      59    
003D A7F7             60            MOV     @R1, SPIDAT   ; move input into memory
003F 09               61            INC     R1            ; increment memory location so new 
                      62                                  ; data is stored in new address
                      63            
0040 B95003           64            CJNE    R1, #50H, CONT ; reset memory location to 40h when 
                      65                                   ; memory location reaches 50h saving
                      66                                   ; 16 bytes of data
                      67    
0043 120088           68            CALL    SNDUART
                      69            
0046 32               70    CONT:   RETI
                      71    
                      72    
                      73    ;====================================================================
                      74    
0060                  75    ORG 0060H                    ; Start code at address above interrupts                   
                      76    
0060                  77    MAIN:                          ; Main program
0060 75D703           78            MOV     PLLCON,#03H
0063 759E83           79            MOV     T3CON,#083h
0066 759D2D           80            MOV     T3FD,#02Dh
0069 759852           81            MOV     SCON,#052h
                      82    
006C 75F824           83            MOV     SPICON,#24h    ; Initialise SPICON to have
                      84                                   ; -Enable SPI serial port
                      85                                   ; -slave mode select
                      86                                   ; -CPOL=0, clk idling low 
                      87                                   ; -CPHA=1
                      88    ; note: it is important to have CPHA in the master and the slave 
                      89    ;       program equal, otherwise uncertainty will exist, as the input
                      90    ;       will be measued during its change of state, and not is at
                      91    ;       its final value.
                      92    
006F 75A901           93            MOV     IEIP2, #01h      ; Enable SPI interrupt
0072 D2AF             94            SETB    EA               ; Enable interrupts
                      95            
0074 7940             96            MOV     R1, #40h       ; initialise R1 to 40 to store the 
                      97                                   ; input data from memory location 40
0076 780A             98            MOV     R0, #0AH       ; initialise R0 to 10
                      99            
0078                 100    TRNSMT: 
0078 08              101            INC     R0
0079 88F7            102            MOV     SPIDAT, R0     ; transmit the current value on R0
007B D200            103            SETB    FLAG           ; set flag so that we wait here until
                     104                                   ; the spi interrupt routine clears
                     105                                   ; the FLAG
                     106    
007D 2000FD          107            JB      FLAG, $        ; stay here until flag is cleared
                     108                                   ; by interrupt
                     109             
                     110    ; check if R0 is equal to 20. If so the number 20 has been 
                     111    ; transmitted and we should reset R0 to 10 to start transmission 
                     112    ; from 11 again.
0080 E8              113            MOV     A, R0 
0081 B414F4          114            CJNE    A, #14H, TRNSMT ; if R0 is not 20, jump to TRNSMT 
0084 780A            115            MOV     R0, #0AH        ; if R0=20 make R0=10 & jump to TRNSMT 
0086 80F0            116            JMP     TRNSMT  
SLAVUART                                                                                                      PAGE 3

                     117    
                     118    
                     119    ; Transmit the values in locations 40h->50h up the UART wait for 
                     120    ; 1 seconds and then transmit and receive values to/from the Master
                     121    ; again down the SPI port.
                     122    
0088                 123    SNDUART: 
0088 B2B4            124            CPL      LED               ;CPL LED with each transmission
008A 900100          125            MOV      DPTR, #TITLE 
008D 1200B4          126            CALL     SENDSTRING        ; write title block on screen
                     127    
0090 7940            128            MOV      R1, #40h          ; move value at address 40 into R2
0092 E7              129            MOV      A, @R1                
0093 FA              130            MOV      R2, A                           
0094                 131    NEXT:                        ; Put new value on a new line
0094 740A            132            MOV      A, #10      ; Transmit a linefeed (= ASCII 10)
0096 1200CC          133            CALL     SENDCHAR
0099 740D            134            MOV      A, #13      ;Transmit a carriage return (=ASCII 13)
009B 1200CC          135            CALL     SENDCHAR
                     136    
009E EA              137            MOV      A, R2        ; Transmit R2 i.e. value @ address R1
009F 1200D4          138            CALL     SENDVAL
00A2 09              139            INC      R1           ; Increment address
00A3 E7              140            MOV      A, @R1
00A4 FA              141            MOV      R2, A        ; R2 holds the value @ addrR1
                     142    
00A5 E9              143            MOV      A, R1           ; Check if at address 50h
00A6 B450EB          144            CJNE     A, #50h, NEXT   ; if not jump to Next 
00A9 0200AC          145            JMP      WAIT1S          ; if so wait 1s and repeat
                     146    
00AC 7464            147    WAIT1S: MOV      A, #100      ; wait for time less than master to
                     148                                  ; synchronise with the master
00AE 1200F4          149            CALL     DELAY
00B1 7940            150            MOV      R1, #40h     ; store new inputs at address 40h again 
00B3 22              151            RET
                     152            
                     153    
                     154    ;____________________________________________________________________
                     155                                                             ; SENDSTRING
                     156    
00B4                 157    SENDSTRING:     ; sends ASCII string to UART starting at location
                     158                    ; DPTR and ending with a null (0) value
                     159    
00B4 C0E0            160            PUSH    ACC