PIC16C63A/65B/73B/74B
REGISTER 10-2: SSPCON: SYNC SERIAL PORT CONTROL REGISTER (ADDRESS 14h)
R/W-0
WCOL
R/W-0
R/W-0
R/W-0
CKP
R/W-0
R/W-0
R/W-0
R/W-0
SSPOV
SSPEN
SSPM3
SSPM2
SSPM1
SSPM0
bit 7
bit 0
bit 7
bit 6
WCOL: Write Collision Flag bit
1= The SSPBUF register was written while still transmitting the previous word (must be
cleared in software)
0= No collision
SSPOV: Synchronous Serial Port Overflow Flag bit
In SPI mode:
1= A new byte was received while the SSPBUF register is still holding the previous unread
data. In case of overflow, the data in SSPSR is lost. Overflow can only occur in Slave
mode. The user must read the SSPBUF, even if only transmitting data, to avoid setting
overflow. In Master mode, the overflow bit is not set since each new reception (and trans-
mission) is initiated by writing to the SSPBUF register.
0= No overflow
In I2C mode:
1= A byte was received while the SSPBUF register is still holding the previous unread byte.
SSPOV is a "don’t care" in transmit mode. SSPOV must be cleared in software in either
mode.
0= No overflow
bit 5
SSPEN: Synchronous Serial Port Enable bit. When enabled, the SSP pins must be properly
configured as input or output.
In SPI mode:
1= Enables serial port and configures SCK, SDO, and SDI as serial port pins
0= Disables serial port and configures these pins as I/O port pins
In I2C mode:
1= Enables the serial port and configures the SDA and SCL pins as serial port pins
0= Disables serial port and configures these pins as I/O port pins
bit 4
CKP: Clock Polarity Select bit
In SPI mode:
1= Idle state for clock is a high level (Microwire default)
0= Idle state for clock is a low level (Microwire alternate)
In I2C mode:
SCK release control
1= Enable clock
0 = Holds clock low (clock stretch). (Used to ensure data setup time.)
bit 3-0
SSPM3:SSPM0: Synchronous Serial Port Mode Select bits
0000= SPI Master mode, clock = FOSC/4
0001= SPI Master mode, clock = FOSC/16
0010= SPI Master mode, clock = FOSC/64
0011= SPI Master mode, clock = TMR2 output/2
0100= SPI Slave mode, clock = SCK pin. SS pin control enabled.
0101= SPI Slave mode, clock = SCK pin. SS pin control disabled. SS can be used as I/O pin.
0110= I2C Slave mode, 7-bit address
0111= I2C Slave mode, 10-bit address
1011= I2C firmware controlled Master mode (Slave idle)
1110= I2C Slave mode, 7-bit address with START and STOP bit interrupts enabled
1111= I2C Slave mode, 10-bit address with START and STOP bit interrupts enabled
Legend:
R = Readable bit
-n = Value at POR
W = Writable bit
U = Unimplemented bit, read as ‘0’
’0’ = Bit is cleared x = Bit is unknown
’1’ = Bit is set
2000 Microchip Technology Inc.
DS30605C-page 57
MICROCHIP [ MICROCHIP ]
