HD6417615 Hitachi Semiconductor, HD6417615 Datasheet - Page 546

• Manufacturer Part Number: HD6417615
• Description: Hardware Manual
• Manufacturer: Hitachi Semiconductor

Table 12.4 Internal Clock Switching and FRC Operation (cont)
No.
3
4
Note: Because the switchover is considered a falling edge, FRC starts counting up.
5. Timer Output (FTOA, FTOB)
During a power-on reset, the timer outputs (FTOA, FTOB) will be unreliable until the
oscillation stabilizes. The initial value is output after the oscillation settling time has elapsed.
Timing of Rewrite of
CKS1 and CKS0 Bits
High-to-low switch
High-to-high switch
FRC Operation
Clock before
Clock before
Clock after
Clock after
FRC clock
FRC clock
switching
switching
switching
switching
FRC
FRC
N
N
Rewrite of CKS bit
N + 1
N + 1
Rewrite of CKS bit
N + 2
N + 2
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