ML51/ML54/ML56
Sep. 01, 2020
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TECHNI
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ML51/M
L54
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L56
Series
Tec
hnical Reference
Manual
5. HIRC cannot be turned off because OCD uses this clock to monitor its internal status. The
instruction that turns off HIRC affects nothing if executing under debug mode. When CPU enters its
Power-down mode under debug mode, HIRC keeps turning on.
The ML51/ML54/ML56 Series OCD system has another limitation that non-intrusive commands cannot
be executed at any time while
the user’s program is running. Non-intrusive commands allow a user to
read or write MCU memory locations or access status and Register Description with the debug
controller. A reading or writing memory or control register space is allowed only when MCU is under
halt condition after a matching of the hardware address breakpoint or a single step running.
