PIC16F877T-20/PT Microchip Technology, PIC16F877T-20/PT Datasheet - Page 258

• Manufacturer Part Number: PIC16F877T-20/PT
• Description: IC MCU FLASH 8KX14 EE 44TQFP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F877T-20/PT

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 33
• Program Memory Size: 14KB (8K x 14)
• 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 8x10b
• Oscillator Type: External
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 44-TQFP, 44-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

PICmicro MID-RANGE MCU FAMILY
16.3.2
DS31016A-page 16-8
Enabling SPI I/O
To enable the serial port, SSP enable bit, SSPEN (SSPCON<5>), must be set. To reset or recon-
figure 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.