M16C65 Datasheet, PDF (69/829 Pages) Renesas Technology Corp – RENESAS MCU M16C FAMILY / M16C/60

Under development
M16C/65 Group
Preliminary Specification
This is a preliminary specification and is subject to change.
2. Central Processing Unit (CPU)
2.8.8 Stack Pointer Select Flag (U Flag)
ISP is selected when the U flag is set to 0. USP is selected when the U flag is set to 1.
The U flag is set to 0 when a hardware interrupt request is acknowledged or the INT instruction of
software interrupt number 0 to 31 is executed.
2.8.9 Processor Interrupt Priority Level (IPL)
IPL is 3 bits wide and assigns processor interrupt priority levels from 0 to 7.
If a requested interrupt has higher priority than IPL, the interrupt is enabled.
2.8.10 Reserved Space
Only write 0 to bits assigned as reserved bits. The read value is undefined.
REJ09B0484-0030 Rev.0.30 Sep 09, 2008
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