Hitachi H8/3937 Series Hardware Manual page 294

Table 10-12 SMR and SCR3 Settings and Clock Source Selection
SMR SCR3
bit 7 bit 1 bit 0
COM CKE1 CKE0 Mode
0 0 0
0 0 1
0 1 0
1 0 0
1 1 0
0 1 1
1 0 1
1 1 1
282
Transmit/Receive Clock
Clock Source SCK
Asynchronous Internal
mode
External
Synchronous Internal
mode
External
Reserved (Do not specify these combinations)
Pin Function
3X
I/O port (SCK pin not used)
3X
Outputs clock with same frequency as bit rate
Outputs clock with frequency 16 times bit rate
Outputs serial clock
Inputs serial clock