Hitachi H8/3637 Hardware Manual page 245

Table 10.12 SMR and SCR3 Settings and Clock Source Selection
SMR SCR3
Bit 7: Bit 1: Bit 0:
COM CKE1 CKE0
0 0 0
1
1 0
1 0 0
1 0
0 1 1
1 0 1
1 1 1
Clock
Mode Source
Asynchronous Internal
mode
External
Synchronous Internal
mode
External
Reserved (illegal settings)
Transmit/Receive Clock
Pin SCK Function
3
I/O port (SCK pin not used)
3
Outputs clock with same frequency as
bit rate
Clock should be input with frequency
16 times the desired bit rate
Outputs a serial clock
Inputs a serial clock
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