DV164136 Microchip Technology, DV164136 Datasheet - Page 211

• Manufacturer Part Number: DV164136
• Description: DEVELOPMENT KIT FOR PIC18
• Manufacturer: Microchip Technology
• Series: PIC®r
• Type: MCUr

Specifications of DV164136

• Contents: Board, Cables, CDs, PICkit™ 3 Programmer, Power Supply
• Processor To Be Evaluated: PIC18F8722, PIC18F87J11
• Interface Type: RS-232, USB
• Operating Supply Voltage: 3.3 V, 5 V
• Silicon Manufacturer: Microchip
• Core Architecture: PIC
• Core Sub-architecture: PIC18
• Silicon Core Number: PIC18F
• Silicon Family Name: PIC18F8xxx
• Kit Contents: PIC18 Exp Brd PICkit 3 Cable CD PSU
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: PIC18F8722, PIC18F87J11
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

19.3.3
To enable the serial port, SSP Enable bit, SSPEN
(SSPxCON1<5>), must be set. To reset or reconfigure
SPI mode, clear the SSPEN bit, reinitialize the
SSPxCON registers and then set the SSPEN bit. This
configures the SDIx, SDOx, SCKx and SSx pins as
serial port pins. For the pins to behave as the serial port
function, some must have their data direction bits (in
the TRIS register) appropriately programmed as
follows:
• SDIx is automatically controlled by the
• SDOx must have the TRISC<5> or TRISD<4> bit
• SCKx (Master mode) must have the TRISC<3> or
• SCKx (Slave mode) must have the TRISC<3> or
• SSx must have the TRISF<7> or TRISD<7> bit
FIGURE 19-2:
© 2008 Microchip Technology Inc.
SPI module
cleared
TRISD<6>bit cleared
TRISD<6> bit set
set
ENABLING SPI I/O
SPI Master SSPM<3:0> = 00xxb
MSb
PROCESSOR 1
Serial Input Buffer
SPI MASTER/SLAVE CONNECTION
Shift Register
(SSPxBUF)
(SSPxSR)
LSb
SDOx
SCKx
SDIx
Serial Clock
Any serial port function that is not desired may be
overridden by programming the corresponding data
direction (TRIS) register to the opposite value.
19.3.4
Figure 19-2 shows a typical connection between two
microcontrollers. The master controller (Processor 1)
initiates the data transfer by sending the SCKx signal.
Data is shifted out of both shift registers on their pro-
grammed clock edge and latched on the opposite edge
of the clock. Both processors should be programmed to
the same Clock Polarity (CKP), then both controllers
would send and receive data at the same time.
Whether the data is meaningful (or dummy data)
depends on the application software. This leads to
three scenarios for data transmission:
• Master sends data – Slave sends dummy data
• Master sends data – Slave sends data
• Master sends dummy data – Slave sends data
PIC18F8722 FAMILY
SDOx
SCKx
SDIx
TYPICAL CONNECTION
SPI Slave SSPM<3:0> = 010xb
MSb
Serial Input Buffer
Shift Register
(SSPxBUF)
PROCESSOR 2
(SSPxSR)
LSb
DS39646C-page 209