R01UH0092EJ0110 Rev.1.10
Page 126 of 807
Jul 31, 2012
M16C/64C Group
9. Power Control
9.4.2
Reading Flash Memory
Current consumption while reading the flash memory can be reduced by using bits FMR22 and FMR23
in the FMR2 register.
9.4.2.1
Slow Read Mode
Slow read mode can be used when f(BCLK) is less than or equal to f(SLOW_R) and the PM17 bit in
the PM1 register is 1 (one wait). Figure 9.4 shows Setting and Canceling Slow Read Mode.
When using 125 kHz on-chip oscillator clock or sub clock as the CPU clock source, a wait is
unnecessary (technical update number: TN-16C-A179A/E).
Figure 9.4
Setting and Canceling Slow Read Mode
Slow read mode
Set the CPU clock to f(SLOW_R) or less
Set the PM17 bit in the PM1 register to 1 (one wait).
Set the FMR22 bit to 0, and then to 1 (enabled)
Processing in slow read mode
Set the FMR22 bit to 0
Completed
Setting
procedure
Canceling
procedure
Содержание M16C Series
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