PIC24FJ64GA104 FAMILY
FIGURE 15-3:
SPI MASTER/SLAVE CONNECTION (STANDARD MODE)
PROCESSOR 1 (SPI Master)
PROCESSOR 2 (SPI Slave)
SDOx
SDIx
Serial Receive Buffer
(SPIxRXB)
Serial Receive Buffer
(SPIxRXB)
SDIx
SDOx
Shift Register
(SPIxSR)
Shift Register
(SPIxSR)
LSb
MSb
MSb
LSb
Serial Transmit Buffer
Serial Transmit Buffer
(SPIxTXB)
(SPIxTXB)
Serial Clock
SCKx
SSx(1)
SCKx
SPIx Buffer
SPIx Buffer
(SPIxBUF)(2)
(SPIxBUF)(2)
SSEN (SPIxCON1<7>) = 1and MSTEN (SPIxCON1<5>) = 0
MSTEN (SPIxCON1<5>) = 1)
Note 1: Using the SSx pin in Slave mode of operation is optional.
2: User must write transmit data to read received data from SPIxBUF. The SPIxTXB and SPIxRXB registers are memory
mapped to SPIxBUF.
FIGURE 15-4:
SPI MASTER/SLAVE CONNECTION (ENHANCED BUFFER MODES)
PROCESSOR 1 (SPI Enhanced Buffer Master)
PROCESSOR 2 (SPI Enhanced Buffer Slave)
SDOx
SDIx
SDIx
SDOx
Shift Register
(SPIxSR)
Shift Register
(SPIxSR)
LSb
MSb
MSb
LSb
8-Level FIFO Buffer
8-Level FIFO Buffer
Serial Clock
SPIx Buffer
SPIx Buffer
SCKx
SSx
SCKx
SSx(1)
(SPIxBUF)(2)
(SPIxBUF)(2)
MSTEN (SPIxCON1<5>) = 1and
SPIBEN (SPIxCON2<0>) = 1
SSEN (SPIxCON1<7>) = 1,
MSTEN (SPIxCON1<5>) = 0and
SPIBEN (SPIxCON2<0>) = 1
Note 1: Using the SSx pin in Slave mode of operation is optional.
2: User must write transmit data to read received data from SPIxBUF. The SPIxTXB and SPIxRXB registers are memory
mapped to SPIxBUF.
DS39951C-page 172
2010 Microchip Technology Inc.
MICROCHIP [ MICROCHIP ]
