Hitachi SH7760 Solution Engine2 Overview page 53

6.2.2 Power Supply Control Register Read Procedure
This subsection describes a procedure for reading the power supply controller registers.
(1) SH7760 issues a read command to a power supply controller.
(2) The power supply controller returns a response to SH7760.
[Note]
(1) Don't issue multiple commands continually from SH7760. Note that the next command must be issued after a
response to the preceding command has been returned from the power supply controller.
6.2.3 Read Command
Figure 6.2 shows a read command format. SH7760 sends a start code, a function code and a register address, in
this order, as a read command.
(1) Start code
(1) Start code
The code is fixed at 0x20.
(2) Function code
• A 1-byte function code specifies the size of data to be read in the lower 4 bits when the upper 4 bits of a function
code are 1000. Figure 6.3 shows a function command where the upper 4 bits are 1000.
• A 2-byte function code specifies the size of data to be read in the lower 12 bits when the upper 4 bits of a
function code are 1001. Figure 6.4 shows a function command where the upper 4 bits are 1001.
D15 D14
1
(3) Register Address
The register address specifies the address of the register to be read
(2) Function code
(1 byte) (1 byte or 2 byte)
D7 D6
1 0
Figure 6.3 Function Command (1 Byte)
D13 D12 D11 D10
0 0 1
Figure 6.4 Function Command (2 Byte)
Figure 6.2 Read Command
D5 D4 D3 D2 D1
0 0 Size of data
D9 D8 D7 D6
Size of data
50
(3) Register address
(2byte)
D0
D5 D4 D3 D2 D1 D0