M16C26 Datasheet, PDF (195/239 Pages) Renesas Technology Corp – 16-BIT CMOS SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/20 SERIES

Udenvdeelropment
Preliminary Specifications Rev. 0.9
Specifications in this manual are tentative and subject to change.
CPU Rewrite Mode (Flash Memory Version)
M16C/26 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
EW1:
In EW1, program code is executed out of the FLASH. First FMR40 (SUSPEND_ENABLE) must be set
to allow the erase-suspend feature. After ther erase command is executed the CPU goes into HOLD.
A maskable interrupt will set FMR41 (SUSPEND_REQUEST) if in an erase operation. Once the erase
is suspended the HOLD is deasserted and execution from the FLASH continues. The interrupt routine
can now be servised, after which control is returned to the main program. If the
SUSPEND_REQUEST has been set, it should be cleared, and when the erase resumes the CPU
goes back into HOLD until the erase operation is complete or another interrupt occurs.
User actions:
1.0 Set FMR40
2.0 Execute erase command out of FLASH.
3.0 HOLD_POINT (in HOLD)
4.0 Maskable Interrupt request. (FMR41 set by h/w)
4.1 Access flash data/code.
4.2 Return
5.0 if FMR41 is set, clear FMR41, jump to HOLD_POINT.
6.0 Continue execution out of FLASH.
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