Applicable Devices
72 73 73A 74 74A 76 77
PIC16C7X
11.3 SPI Mode for PIC16C76/77
This section contains register definitions and opera-
tional characteristics of the SPI module on the
PIC16C76 and PIC16C77 only.
FIGURE 11-7: SSPSTAT: SYNC SERIAL PORT STATUS REGISTER (ADDRESS 94h)(PIC16C76/77)
R/W-0 R/W-0 R-0
R-0
R-0
R-0
R-0
R-0
SMP CKE D/A
P
S
R/W
UA
bit7
bit 7:
SMP: SPI data input sample phase
SPI Master Mode
1 = Input data sampled at end of data output time
0 = Input data sampled at middle of data output time
SPI Slave Mode
SMP must be cleared when SPI is used in slave mode
BF
bit0
R = Readable bit
W = Writable bit
U = Unimplemented bit,
read as ‘0’
- n =Value at POR reset
bit 6:
bit 5:
bit 4:
bit 3:
bit 2:
bit 1:
CKE: SPI Clock Edge Select (Figure 11-11, Figure 11-12, and Figure 11-13)
CKP = 0
1 = Data transmitted on rising edge of SCK
0 = Data transmitted on falling edge of SCK
CKP = 1
1 = Data transmitted on falling edge of SCK
0 = Data transmitted on rising edge of SCK
D/A: Data/Address bit (I2C mode only)
1 = Indicates that the last byte received or transmitted was data
0 = Indicates that the last byte received or transmitted was address
P: Stop bit (I2C mode only. This bit is cleared when the SSP module is disabled, or when the Start bit is
detected last, SSPEN is cleared)
1 = Indicates that a stop bit has been detected last (this bit is '0' on RESET)
0 = Stop bit was not detected last
S: Start bit (I2C mode only. This bit is cleared when the SSP module is disabled, or when the Stop bit is
detected last, SSPEN is cleared)
1 = Indicates that a start bit has been detected last (this bit is '0' on RESET)
0 = Start bit was not detected last
R/W: Read/Write bit information (I2C mode only)
This bit holds the R/W bit information following the last address match. This bit is only valid from the
address match to the next start bit, stop bit, or ACK bit.
1 = Read
0 = Write
UA: Update Address (10-bit I2C mode only)
1 = Indicates that the user needs to update the address in the SSPADD register
0 = Address does not need to be updated
bit 0:
BF: Buffer Full Status bit
Receive (SPI and I2C modes)
1 = Receive complete, SSPBUF is full
0 = Receive not complete, SSPBUF is empty
Transmit (I2C mode only)
1 = Transmit in progress, SSPBUF is full
0 = Transmit complete, SSPBUF is empty
© 1997 Microchip Technology Inc.
DS30390E-page 83