Datasheet
Data Sheet ADuC7124/ADuC7126
Rev. C | Page 77 of 108
I
2
C Slave Receive Registers
Name: I2C0SRX, I2C1SRX
Address: 0xFFFF0830, 0xFFFF0930
Default Value: 0x00
Access: Read
Function: This 8-bit MMR is the I
2
C slave receive register.
I
2
C Slave Transmit Registers
Name: I2C0STX, I2C1STX
Address: 0xFFFF0834, 0xFFFF0934
Default Value: 0x00
Access: Write
Function: This 8-bit MMR is the I
2
C slave transmit register.
I
2
C Hardware General Call Recognition Registers
Name: I2C0ALT, I2C1ALT
Address: 0xFFFF0838, 0xFFFF0938
Default Value: 0x00
Access: Read/write
Function: This 8-bit MMR is used with hardware general
calls when I2CxSCON Bit 3 is set to 1. This
register is used in cases where a master is unable
to generate an address for a slave, and instead, the
slave must generate the address for the master.
I
2
C Slave Device ID Registers
Name: I2C0IDx, I2C1IDx
Addresses: 0xFFFF093C = I2C1ID0
0xFFFF083C = I2C0ID0
0xFFFF0940 = I2C1ID1
0xFFFF0840 = I2C0ID1
0xFFFF0944 = I2C1ID2
0xFFFF0844 = I2C0ID2
0xFFFF0948 = I2C1ID3
0xFFFF0848 = I2C0ID3
Default Value: 0x00
Access: Read/write
Function: These 8-bit MMRs are programmed with I
2
C
bus IDs of the slave. See the I2C Bus Addresses
section for further details.
I
2
C Common Registers
I
2
C FIFO Status Register
Name: I2C0FSTA, I2C1FSTA
Address: 0xFFFF084C, 0xFFFF094C
Default Value: 0x0000
Access: Read/write
Function: These 16-bit MMRs contain the status of the
Rx/Tx FIFOs in both master and slave modes.
Table 111. I2CxFSTA MMR Bit Descriptions
Bit Name Description
[15:10] Reserved.
9 I2CFMTX
Set this bit to 1 to flush the master Tx
FIFO.
8 I2CFSTX Set this bit to 1 to flush the slave Tx FIFO.
[7:6] I2CMRXSTA I
2
C master receive FIFO status bits.
[00] = FIFO empty.
[01] = byte written to FIFO.
[10] = one byte in FIFO.
[11] = FIFO full.
[5:4] I2CMTXSTA I
2
C master transmit FIFO status bits.
[00] = FIFO empty.
[01] = byte written to FIFO.
[10] = one byte in FIFO.
[11] = FIFO full.
[3:2] I2CSRXSTA I
2
C slave receive FIFO status bits.
[00] = FIFO empty.
[01] = byte written to FIFO.
[10] = one byte in FIFO.
[11] = FIFO full.
[1:0] I2CSTXSTA I
2
C slave transmit FIFO status bits.
[00] = FIFO empty.
[01] = byte written to FIFO.
[10] = one byte in FIFO.
[11] = FIFO full.