Table of Contents
Advertisement
Transactions
2
I
C transactions control the SE4750, where a transaction consists of a command followed by a response. I
master/slave protocol, meaning the host initiates both transmissions.
The SE4750 typically processes a command in less than 1 ms, but some commands take up to 100 ms. For this
reason, after sending a command, the host (I
respond the host should retry the response request for up to 100 ms. If the SE4750 does not respond within this
time, a hard failure occurred.
2
The I
C format of these commands and responses is as follows.
2
I
C Command Format
<I2C-Start Bit> <SLA-W> <Cmd-Opcode> <[SE4750-Cmd-Data]> <Checksum> <I2C-Stop-Bit>
where:
•
I2C-Start-Bit and I2C-Stop-Bit are as defined by the I
•
SLA-W is 0xB8 (Slave-Addr + Write-Op) or
• Slave Address is 0x5C (or 0xB8 after shifting into 7 MSBs)
• Write-Op is 0x00
•
Opcode is 1 byte from the SE4750 Command Op column in
•
[SE4750-Cmd-Data] is from the SE4750 Command Data column in
NULL.
•
Checksum is a 1 byte checksum of the SE4750 Cmd Data bytes. See
2
I
C Response Format
<I2C-Start Bit> <SLA-R> <Rsp-Opcode> <Status> <[SE4750-Rsp-Data]> <I2C-Stop-Bit>
Where:
•
I2C-Start-Bit and I2C-Stop-Bit are as defined by the I
•
SLA-R is 0xB9 (Slave-Addr + Read-Op) or
• Slave Address is 0x5C (or 0xB8 after shifting into 7 msb's)
• Read-Op is 0x01
•
Opcode is 1 byte from the SE4750 Response Op column in
•
Status indicates whether the SE4750 successfully processed the command. See
page
5-4.
•
[SE4750-Rsp-Data] is from the SE4750 Response Data column in
2
C master) should request a response, and if the SE4750 does not
2
C specification
Table 5-3 on page
2
C specification
Table 5-3 on page
Control Interface
5-9.
Table 5-3 on page
5-9. This can be
Command Checksum on page
5-9.
Response Status Code on
Table 5-3 on page
5-9. This can be NULL.
5 - 3
2
C is a
5-4.
Advertisement
Table of Contents
