Datasheet

Table Of Contents
1998-2013 Microchip Technology Inc. DS30292D-page 37
PIC16F87X
REGISTER 3-1: TRISE REGISTER (ADDRESS 89h)
R-0 R-0 R/W-0 R/W-0 U-0 R/W-1 R/W-1 R/W-1
IBF OBF IBOV PSPMODE
Bit2 Bit1 Bit0
bit 7 bit 0
Parallel Slave Port Status/Control Bits:
bit 7 IBF: Input Buffer Full Status bit
1 = A word has been received and is waiting to be read by the CPU
0 = No word has been received
bit 6 OBF: Output Buffer Full Status bit
1 = The output buffer still holds a previously written word
0 = The output buffer has been read
bit 5 IBOV: Input Buffer Overflow Detect bit (in Microprocessor mode)
1 = A write occurred when a previously input word has not been read (must be cleared in
software)
0 = No overflow occurred
bit 4 PSPMODE: Parallel Slave Port Mode Select bit
1 = PORTD functions in Parallel Slave Port mode
0 = PORTD functions in general purpose I/O mode
bit 3 Unimplemented: Read as '0'
PORTE Data Direction Bits:
bit 2 Bit2: Direction Control bit for pin RE2/CS/AN7
1 = Input
0 = Output
bit 1 Bit1: Direction Control bit for pin RE1/WR
/AN6
1 = Input
0 = Output
bit 0 Bit0: Direction Control bit for pin RE0/RD
/AN5
1 = Input
0 = Output
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
- n = Value at POR ’1’ = Bit is set 0’ = Bit is cleared x = Bit is unknown