PIC16F876AT-I/SO Microchip Technology, PIC16F876AT-I/SO Datasheet - Page 228

• Manufacturer Part Number: PIC16F876AT-I/SO
• Description: IC MCU CMOS 20MHZ 8K FLSH 28SOIC
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F876AT-I/SO

• Core Size: 8-Bit
• Program Memory Size: 14KB (8K x 14)
• Core Processor: PIC
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 22
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 368 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Data Converters: A/D 5x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-SOIC (7.5mm Width)
• Controller Family/series: PIC16F
• No. Of I/o's: 22
• Eeprom Memory Size: 256Byte
• Ram Memory Size: 368Byte
• Cpu Speed: 20MHz
• No. Of Timers: 3
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

PICmicro MID-RANGE MCU FAMILY
15.3.2
DS31015A-page 15-8
Enabling SPI I/O
To enable the serial port the SSP Enable bit, SSPEN (SSPCON<5>), must be set. To reset or
reconfigure SPI mode, clear the SSPEN bit which re-initializes the SSPCON register, and then
set the SSPEN bit. This configures the SDI, SDO, SCK, and SS pins as serial port pins. For the
pins to behave as the serial port function, they must have their data direction bits (in the TRIS
register) appropriately programmed. That is:
• SDI must have the TRIS bit set
• SDO must have the TRIS bit cleared
• SCK (Master mode) must have the TRIS bit cleared
• SCK (Slave mode) must have the TRIS bit set
• SS must have the TRIS bit set
Any serial port function that is not desired may be overridden by programming the corresponding
data direction (TRIS) register to the opposite value. An example would be in master mode where
you are only sending data (to a display driver), then both SDI and SS could be used as general
purpose outputs by clearing their corresponding TRIS register bits.
1997 Microchip Technology Inc.