S7760A Datasheet, PDF (26/54 Pages) Seiko Instruments Inc – PROGRAMMABLE PORT CONTROLLER (PORT EXPANDER WITH BUILT-IN E2PROM CIRCUIT)

PROGRAMMABLE PORT CONTROLLER (PORT EXPANDER WITH BUILT-IN E²PROM CIRCUIT)
S-7760A
Rev.2.0_01
 Example of Flowchart for Software
1. Read/Write in register
The example of flowchart for software when accessing to the control port register is shown in Figure 29.
START
Switching access to
E²PROM/register
1-byte command
(ST, DC2 to 0, 0001, 0, ACK, SP)^*1
Access to
control port register
END
2-byte command
• Write
(ST, DC2 to 0, 0101, 0, ACK, CTR7 to 0, ACK, SP)^*1
• Read
(ST, DC2 to 0, 0101, 1, ACK, CTR7 to 0, ACK, SP)^*1
*1. ST
DC2 to 0
ACK
CTR7 to 0
SP
: Start condition
: Device code
: Acknowledgment
: Control port register
: Stop condition
Figure 29 Flowchart for Software Example 1
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