Datasheet

Table Of Contents
PIC18F2525/2620/4525/4620
DS39626E-page 172 © 2008 Microchip Technology Inc.
REGISTER 17-4: SSPCON1: MSSP CONTROL REGISTER 1 (I
2
C™ MODE)
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
WCOL SSPOV SSPEN
(1)
CKP SSPM3 SSPM2 SSPM1 SSPM0
bit 7 bit 0
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
bit 7 WCOL: Write Collision Detect bit
In Master Transmit mode:
1 = A write to the SSPBUF register was attempted while the I
2
C conditions were not valid for a
transmission to be started (must be cleared in software)
0 = No collision
In Slave Transmit mode:
1 = The SSPBUF register is written while it is still transmitting the previous word (must be cleared in
software)
0 = No collision
In Receive mode (Master or Slave modes):
This is a “don’t care” bit.
bit 6 SSPOV: Receive Overflow Indicator bit
In Receive mode:
1 = A byte is received while the SSPBUF register is still holding the previous byte (must be cleared in
software)
0 = No overflow
In Transmit mode:
This is a “don’t care” bit in Transmit mode.
bit 5 SSPEN: Master Synchronous Serial Port Enable bit
(1)
1 = Enables the serial port and configures the SDA and SCL pins as the serial port pins
0 = Disables serial port and configures these pins as I/O port pins
bit 4 CKP: SCK Release Control bit
In Slave mode:
1 = Releases clock
0 = Holds clock low (clock stretch), used to ensure data setup time
In Master mode:
Unused in this mode.
bit 3-0 SSPM3:SSPM0: Master Synchronous Serial Port Mode Select bits
(2)
1111 = I
2
C Slave mode, 10-bit address with Start and Stop bit interrupts enabled
1110 = I
2
C Slave mode, 7-bit address with Start and Stop bit interrupts enabled
1011 = I
2
C Firmware Controlled Master mode (Slave Idle)
1000 = I
2
C Master mode, clock = FOSC/(4 * (SSPADD + 1))
0111 = I
2
C Slave mode, 10-bit address
0110 = I
2
C Slave mode, 7-bit address
Bit combinations not specifically listed here are either reserved or implemented in SPI mode only.
Note 1: When enabled, the SDA and SCL pins must be properly configured as inputs or outputs.