Microchip Technology MA330020 Data Sheet

 2008-2014 Microchip Technology Inc.

DS70000318G-page 219

The Serial Peripheral Interface (SPI) module is a
synchronous serial interface useful for communicating
with other peripheral or microcontroller devices. These
peripheral devices can be serial EEPROMs, shift
registers, display drivers, Analog-to-Digital Converters
and so on. The SPI module is compatible with SPI and
SIOP from Motorola

®

.

The SPI module consists of a 16-bit shift register,
SPIxSR (where x = 1), used for shifting data in and out,
and a buffer register, SPIxBUF. A control register,
SPIxCON, configures the module. Additionally, a status
register, SPIxSTAT, indicates status conditions.

The serial interface consists of the following four pins:

• SDIx (Serial Data Input)

• SDOx (Serial Data Output)

• SCKx (Shift Clock Input Or Output)

• SSx (Active-Low Slave Select).

In Master mode operation, SCK is a clock output; in
Slave mode, it is a clock input.

Note 1: This data sheet summarizes the features

of the dsPIC33FJ06GS101/X02 and
dsPIC33FJ16GSX02/X04 families of
devices. It is not intended to be a
comprehensive reference source. To
complement the information in this data
sheet, refer to “Serial Peripheral
Interface (SPI)” (DS70206) in the
“dsPIC33F/PIC24H Family Reference
Manual”, which is available on the
Microchip web site (

www.microchip.com

).

2: Some registers and associated bits

described in this section may not be
available on all devices. Refer to

 in

this data sheet for device-specific register
and bit information.

Internal Data Bus

SDIx

SDOx

SSx

SCKx

SPIxSR

bit 0

Shift Control

Edge

Select

F

CY

Primary

1:1/4/16/64

Enable 

Prescaler

Sync

SPIxBUF

Control

Transfer

Transfer

Write SPIxBUF

Read SPIxBUF

16

SPIxCON1<1:0>

SPIxCON1<4:2>

Master Clock

Clock

Control

Secondary

Prescaler

1:1 to 1:8

SPIxRXB

SPIxTXB