EP80579 Datasheet, PDF (920/1916 Pages) Intel Corporation – Intel® EP80579 Integrated Processor Product Line

Intel^® EP80579 Integrated Processor
24.4.2.3
Write Byte/Word
The first byte of a write byte/word access is the command code. The next one or two
bytes are the data to be written. When programmed for a write byte/word command,
the Transmit Slave Address, device command, and Data0 Registers are sent. In
addition, the Data1 Register is sent on a write word command. The order of bits
without PEC is shown in Table 24-34. Issuing a write byte/word command with I2C_EN
set produces undefined results. Software must force the I2C_EN bit to 0 when running
this command.
The order of bits with PEC is shown in Table 24-35.
Table 24-34. Write Byte/Word Protocol Without PEC
Write Byte Protocol
Write Word Protocol
Bit
Description
1
Start
2 – 8 Slave Address - 7 bits
9
Write
10 Acknowledge from slave
11 – 18 Command code - 8 bits
19 Acknowledge from slave
20 – 27 Data Byte - 8 bits
28 Acknowledge from Slave
29 Stop
Bit
Description
1
Start
2 – 8 Slave Address - 7 bits
9
Write
10 Acknowledge from slave
11 – 18 Command code - 8 bits
19 Acknowledge from slave
20 – 27 Data Byte Low - 8 bits
28 Acknowledge from Slave
29 – 36 Data Byte High - 8 bits
37 Acknowledge from slave
38 Stop
Table 24-35. PEC Bit Order
Write Byte Protocol
Bit
Description
1
Start
2 – 8 Slave Address - 7 bits
9
Write
10 Acknowledge from slave
11 – 18 Command code - 8 bits
19 Acknowledge from slave
20 – 27 Data Byte - 8 bits
28 Acknowledge from Slave
29 – 36 PEC
37 Acknowledge from Slave
38 Stop
Write Word Protocol
Bit
Description
1
Start
2 – 8 Slave Address - 7 bits
9
Write
10 Acknowledge from slave
11 – 18 Command code - 8 bits
19 Acknowledge from slave
20 – 27 Data Byte Low - 8 bits
28 Acknowledge from Slave
29 – 36 Data Byte High - 8 bits
37 Acknowledge from slave
38 – 45 PEC
46 Acknowledge from slave
47 Stop
Intel^® EP80579 Integrated Processor Product Line Datasheet
920
August 2009
Order Number: 320066-003US