VersaLogic Python EBX-11, Справочное руководство

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Interfaces and Connectors
EBX-11 Reference manual
53
MOV AL, 44h ;SPIDATA1: Mirror & Open-Drain interrupts
OUT DX, AL
MOV DX, 1DCh
MOV AL, 0Ah ;SPIDATA2: MCP23S17 address 0x0A
OUT DX, AL
MOV DX, 1DDh
MOV AL, 40h ;SPIDATA3: MCP23S17 write command
OUT DX, AL
BUSY: MOV DX, 1D9h
IN AL, DX ;Get SPI status
AND AL, 01h ;Isolate the BUSY bit
JNZ BUSY ;Loop back if SPI transaction is not complete
MOV DX, 1D8h
MOV AL, 27h ;SPICONTROL: SPI Mode 00, 24bit, auto DIO_1_SS#
OUT DX, AL
MOV DX, 1D9h
MOV AL, 30h ;SPISTATUS: 8MHz, no IRQ, left-shift
OUT DX, AL
MOV DX, 1DBh
MOV AL, 44h ;SPIDATA1: Mirror & Open-Drain interrupts
OUT DX, AL
MOV DX, 1DCh
MOV AL, 0Ah ;SPIDATA2: MCP23S17 address 0x0A
OUT DX, AL
MOV DX, 1DDh
MOV AL, 40h ;SPIDATA3: MCP23S17 write command
OUT DX, AL
W
RITING TO A
D
IGITAL
I/O P
ORT
The following code example initiates a write of 55h to Digital I/O port bits DIO15-DIO8.
;Write 44h to configure MCP23S17 register IOCON
MOV DX, 1D8h
MOV AL, 26h ;SPICONTROL: SPI Mode 00, 24bit, DIO_0_SS#
OUT DX, AL
MOV DX, 1D9h
MOV AL, 30h ;SPISTATUS: 8MHz, no IRQ, left-shift
OUT DX, AL
MOV DX, 1DBh
MOV AL, 44h ;SPIDATA1: mirror and open-drain interrupts
OUT DX, AL
MOV DX, 1DCh
MOV AL, 0Ah ;SPIDATA2: MCP23S17 IOCON register address 0Ah
OUT DX, AL
MOV DX, 1DDh
MOV AL, 40h ;SPIDATA3: MCP23S17 write command
OUT DX, AL
CALL BUSY ;Poll busy flag to wait for SPI transaction
;Configure MCP23S17 register IODIRA for outputs
MOV DX, 1DBh
MOV AL, 00h ;SPIDATA1: 00h for outputs
OUT DX, AL
MOV DX, 1DCh
MOV AL, 00h ;SPIDATA2: MCP23S17 register address 00h
OUT DX, AL
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