HD64336900G Datasheet, PDF (102/408 Pages) Renesas Technology Corp – 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Tiny Series

LSI operates on
internal RC clock
Start
(LSI operates on internal RC clock)
Write 0 to OSCBAKE in CKCSR
[1] When 0 is written to the OSCSEL bit, this LSI
switches the external clock to the internal RC clock
after the φ stop duration. Seven rising edges of the
φ_RC clock after the OSCSEL bit becomes 0 are
included in the φ stop duration.
[2] Writing 0 to PMRC0 stops the external oscillation.
Write 1 to CKSWIE in CKCSR
if necessary
Write 0 to OSCSEL in CKCSR [1]
LSI operates on
internal RC clock
When CKSWIE = 1
Exception handling
for clock switching
Write 0 to PMRC0 in CKCSR
[2]
if necessary
LSI operates on internal oscillator
Figure 5.5 Flowchart of Clock Switching with Backup Function Disabled (2)
(From External Clock to Internal RC Clock)
Rev. 1.00, 11/03, page 74 of 376