[ บทความ : ตัวอย่างสำหรับ 68HC11 V2 ตอนที่ 10 ] ทดสอบติดต่อกับ SPI Interface

หมายเหตุ ตัวอย่างโปรแกรมนี้ใช้กับบอร์ด74HC595(ET-7LSD)

ตัวอย่างซอร์สโค้ดสำหรับติดต่อกับระบบ SPI Interface กับบอร์ด CP-68HC11 V2 สำหรับการเขียนเพื่อเป็นโปรแกรมมอนิเตอร์เป็นดังนี้

;/**********************************/; ;/* Demo Program For SPI Interface */; ;/* Hardware : ET-CP68HC11 Ver 2.0 */; ;/* Complier : AS11NEW.EXE (V1.03) */; ;/**********************************/; ; ;/* Interface SPI With 74HC595(ET-7LSD) ;/* MISO (PD2) -- NC ;/* MOSI (PD3) -- DATA (14) ;/* SCK (PD4) -- SHIFT (11) ;/* SS# (PD5) -- LATCH (12) ; PORTD EQU $1008 ; PortD Data Register DDRD EQU $1009 ; PortD Data Direction SPCR EQU $1028 ; SPI Control Register SPSR EQU $1029 ; SPI Status Register SPDR EQU $102A ; SPI Data Register ORG $A000 ; Start at Rom Monitor MAIN LDS #$9FFF ; Stack on RAM 32KB LDX #$1000 ; Base Register JSR INIT_SPI LOOP1 LDAB #10 LDY #TAB_SEG ; 7-Segment Code 0-9 LOOP2 LDAA 0,Y JSR TX_SPI ; Display 7LSD JSR DELAY INY DECB BNE LOOP2 BRA LOOP1 ;/*********************************/; ;/* Initial SPCR For SPI Port */; ;/* SPIE = 0 : Interupt Disable */; ;/* SPE = 1 : SPI System ON */; ;/* DWOM = 0 : Output Push-Pull */; ;/* MSTR = 1 : SPI = Master */; ;/* CPOL = 0 : Clock Active High */; ;/* CPHA = 0 : Slave Latch Rising */; ;/* SPSR0,SPSR1 = 11 : Clock / 32 */; ;/*********************************/; ; INIT_SPI PSHA ; Save Register LDAA #%00111000 STAA $1009 ; PD5 (SS),PD4(SCK),PD3(MOSI)=Output LDAA #%01010011 STAA $1028 ; SPCR SPI Control Register PULA ; Restore Register RTS ;/***************************/; ;/* Send Data 1 Byte to SPI */; ;/* Input : ACC (8Bit-Data) */; ;/***************************/; ; TX_SPI PSHX ; Save Register LDX #$1000 ; Base Address Register BCLR $08,X %00100000 ; PortD (SS = Low Falling Edge) STAA SPDR ; Store Data for Send TX_SPI1 LDAA $1029 ; SPSR (SPI Status) BPL TX_SPI1 BSET $08,X %00100000 ; PortD (SS = High Rising Edge) PULX ; Restore Register RTS ;/*****************************/; ;/* Delay 0.5 Sec at E = 2MHz */; ;/*****************************/; ; DELAY PSHX PSHB LDAB #$50 DLY10 LDX #$0D06 ; 10 mSec counter DLY20 DEX BNE DLY20 DECB BNE DLY10 ; 10mSec x 50 = 0.5 Second PULB PULX RTS ;/*******************/; ;/* Table 7 Segment */; ;/*******************/; ; TAB_SEG FCB $3F,$06,$5B,$4F ; 0 1 2 3 FCB $66,$6D,$7D,$07 ; 4 5 6 7 FCB $7F,$6F ; 8 9 ORG $FFFE ; Reset Vectot FDB MAIN END

ส่วนสำหรับเขียนเพื่อทำงานกับมอนิเตอร์ของอีทีที จะเป็นดังนี้

;/**********************************/; ;/* Demo Program For SPI Interface */; ;/* Hardware : ET-CP68HC11 Ver 2.0 */; ;/* Complier : AS11NEW.EXE (V1.03) */; ;/**********************************/; ; ;/* Interface SPI With 74HC595(ET-7LSD) ;/* MISO (PD2) -- NC ;/* MOSI (PD3) -- DATA (14) ;/* SCK (PD4) -- SHIFT (11) ;/* SS# (PD5) -- LATCH (12) ; PORTD EQU $1008 ; PortD Data Register DDRD EQU $1009 ; PortD Data Direction SPCR EQU $1028 ; SPI Control Register SPSR EQU $1029 ; SPI Status Register SPDR EQU $102A ; SPI Data Register ORG $2200 ; Start of Debugger User Area MAIN LDX #$1000 ; Base Register JSR INIT_SPI LOOP1 LDAB #10 LDY #TAB_SEG ; 7-Segment Code 0-9 LOOP2 LDAA 0,Y JSR TX_SPI ; Display 7LSD JSR DELAY INY DECB BNE LOOP2 BRA LOOP1 ;/*********************************/; ;/* Initial SPCR For SPI Port */; ;/* SPIE = 0 : Interupt Disable */; ;/* SPE = 1 : SPI System ON */; ;/* DWOM = 0 : Output Push-Pull */; ;/* MSTR = 1 : SPI = Master */; ;/* CPOL = 0 : Clock Active High */; ;/* CPHA = 0 : Slave Latch Rising */; ;/* SPSR0,SPSR1 = 11 : Clock / 32 */; ;/*********************************/; ; INIT_SPI PSHA ; Save Register LDAA #%00111000 STAA $1009 ; PD5 (SS),PD4(SCK),PD3(MOSI)=Output LDAA #%01010011 STAA $1028 ; SPCR SPI Control Register PULA ; Restore Register RTS ;/***************************/; ;/* Send Data 1 Byte to SPI */; ;/* Input : ACC (8Bit-Data) */; ;/***************************/; ; TX_SPI PSHX ; Save Register LDX #$1000 ; Base Address Register BCLR $08,X %00100000 ; PortD (SS = Low Falling Edge) STAA SPDR ; Store Data for Send TX_SPI1 LDAA $1029 ; SPSR (SPI Status) BPL TX_SPI1 BSET $08,X %00100000 ; PortD (SS = High Rising Edge) PULX ; Restore Register RTS ;/*****************************/; ;/* Delay 0.5 Sec at E = 2MHz */; ;/*****************************/; ; DELAY PSHX PSHB LDAB #$50 DLY10 LDX #$0D06 ; 10 mSec counter DLY20 DEX BNE DLY20 DECB BNE DLY10 ; 10mSec x 50 = 0.5 Second PULB PULX RTS ;/*******************/; ;/* Table 7 Segment */; ;/*******************/; ; TAB_SEG FCB $3F,$06,$5B,$4F ; 0 1 2 3 FCB $66,$6D,$7D,$07 ; 4 5 6 7 FCB $7F,$6F ; 8 9 END

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