PIC18FXX20
REGISTER 10-1: PSPCON REGISTER
R-0
IBF
R-0
OBF
R/W-0
IBOV
R/W-0
PSPMODE
U-0
—
U-0
—
U-0
—
U-0
—
bit 7
bit 0
bit 7
bit 6
bit 5
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
OBF: Output Buffer Full Status bit
1= The output buffer still holds a previously written word
0= The output buffer has been read
IBOV: Input Buffer Overflow Detect bit
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= Parallel Slave Port mode
0= General Purpose I/O mode
bit 3-0
Unimplemented: Read as ‘0’
Legend:
R = Readable bit
- n = Value at POR
W = Writable bit
‘1’ = Bit is set
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared x = Bit is unknown
FIGURE 10-24:
PARALLEL SLAVE PORT WRITE WAVEFORMS
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
CS
WR
RD
PORTD<7:0>
IBF
OBF
PSPIF
2003 Microchip Technology Inc.
Advance Information
DS39609A-page 129