pic32mx320f064h Microchip Technology Inc., pic32mx320f064h Datasheet - Page 326

• Manufacturer Part Number: pic32mx320f064h
• Description: 64/100-pin General Purpose, 32-bit Flash Microcontrollers
• Manufacturer: Microchip Technology Inc.

PIC32MX FAMILY
17.2
The PIC32MX SPI module operates in normal Master
or Slave modes and offers the following additional
modes:
• Framed Master
• Framed Slave
• 8, 16, 32-Bit Data Width Transfers
• Slave Select (Slave mode only)
Below is a typical system Master – Slave connection
diagram.
17.2.1
The PIC32MX SPI module allows three types of data
widths when transmitting and receiving data over an
SPI bus. The selection of data width determines the
minimum length of SPI data.
FIGURE 17-2:
DS61143A-page 324
Note 1: Using the SSx pin in Slave mode of operation is optional.
Master and Slave Modes
2: User must write transmit data to SPIxBUF and read received data from SPIxBUF. The SPIxTXB and SPIxRXB
8, 16, 32-BIT OPERATION
registers are memory mapped to SPIxBUF.
MSB
Serial Transmit Buffer
Serial Receive Buffer
SPI MASTER/SLAVE CONNECTION
[SPI Master]
PIC32MX
Shift Register
(SPIxRXB)
(SPIxTXB)
(SPIxBUF)
SPI Buffer
(SPIxSR)
MSTEN (SPIxCON<5>
(2)
(2)
LSB
GPIO/SSx
Advance Information
SDOx
SDIx
SCKx
) = 1
Serial Clock
.
Two
(SPIxCON<11:10>), define the mode of operation. To
change the mode of operation on the fly, the SPI mod-
ule must be idle, i.e., not performing any transactions.
If the SPI module is switched off (SPIxCON<15> = 0),
the new mode will be available when the module is
again switched on.
The number of clock pulses at the SCKx pin are depen-
dent on the selected mode of operation. For 8-Bit mode,
8 clocks; for 16-Bit mode, 16 clocks; and for 32-Bit
mode, 32 clocks are required.
SSEN (SPIxCON<7>)
MSTEN (SPIxCON<5>)
SDIx
SDOx
SCKx
SSx
control
(1)
MSB
Serial Receive Buffer
Serial Transmit Buffer
bits,
PROCESSOR 2
Shift Register
(SPIxRXB)
(SPIxSR)
(SPIxTXB)
(SPIxBUF)
[SPI Slave]
SPI Buffer
= 1
© 2007 Microchip Technology Inc.
= 0
MODE32
and
LSB
and
MODE16