W79E825A Datasheet, PDF (33/127 Pages) Winbond – 8-BIT MICROCONTROLLER

W79E825A/824A/823B/822B Data Sheet
SLAVE ADDRESS MASK ENABLE
Bit: 7
6
5
4
3
2
1
0
SADEN.7 SADEN.6 SADEN.5 SADEN.4 SADEN.3 SADEN.2 SADEN.1 SADEN.0
Mnemonic: SADEN
Address: B9h
BIT
NAME
FUNCTION
This register enables the Automatic Address Recognition feature of the Serial
port 0. When a bit in the SADEN is set to 1, the same bit location in SADDR
7-0
SADEN [7:0]
will be compared with the incoming serial data. When SADEN is 0, then the
bit becomes a "don't care" in the comparison. This register enables the
Automatic Address Recognition feature of the Serial port 0. When all the bits
of SADEN are 0, interrupt will occur for any incoming address.
SLAVE ADDRESS MASK ENABLE 1
Bit: 7
I2DAT.7
6
I2DAT.6
5
I2DAT.5
4
I2DAT.4
Mnemonic: I2DAT
BIT NAME
7-0 I2DAT.[7:0] The data register of I2C.
3
I2DAT.3
2
I2DAT.2
FUNCTION
1
0
I2DAT.1 I2DAT.0
Address: BCh
I2C STATUS REGISTER
Bit: 7
6
5
4
3
2
1
0
I2STATUS.7 I2STATUS.6 I2STATUS.5 I2STATUS.4 I2STATUS.3 -
-
-
Mnemonic: I2STATUS
Address: BDh
BIT
NAME
FUNCTION
The status register of I2C:
The three least significant bits are always 0. The five most significant bits
contain the status code. There are 23 possible status codes. When
I2STATUS contains F8H, no serial interrupt is requested. All other
I2STATUS values correspond to defined I2C states. When each of these
7-0 I2STATUS.[7:0] ^{states is entered, a status interrupt is requested (SI = 1). A valid status}
code is present in I2STATUS one machine cycle after SI is set by hardware
and is still present one machine cycle after SI has been reset by software.
In addition, states 00H stands for a Bus Error. A Bus Error occurs when a
START or STOP condition is present at an illegal position in the formation
frame. Example of illegal position are during the serial transfer of an
address byte, a data byte or an acknowledge bit.
I2C BAUD RATE CONTROL REGISTER
Bit: 7
6
5
4
I2CLK.7 I2CLK.6 I2CLK.5 I2CLK.4
Mnemonic: I2CLK
3
I2CLK.3
2
I2CLK.2
1
0
I2CLK.1 I2CLK.0
Address: BEh
- 33 -
Publication Release Date: February 21, 2008
Revision A9