M38503MXH Datasheet, PDF (37/86 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER

MITSUBISHI MICROCOMPUTERS
3850 Group (Spec. H)
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Reset
Middle-speed mode
(f(φ) = 1 MHz)
CM7 = 0
CM6 = 1
CM5 = 0 (8 MHz oscillating)
CM4 = 0 (32 kHz stopped)
C M6
“1” ←→ “0”
High-speed mode
(f(φ) = 4 MHz)
CM7 = 0
CM6 = 0
CM5 = 0 (8 MHz oscillating)
CM4 = 0 (32 kHz stopped)
“^0”
CM_“1⁴_”C^←_M“1^→_{6” ←→} “0^”
“_1”^C_←^M“0_→6^{”C←M}→⁴ _{“1”}
“_0”
Middle-speed mode
(f(φ) = 1 MHz)
CM7 = 0
CM6 = 1
CM5 = 0 (8 MHz oscillating)
CM4 = 1 (32 kHz oscillating)
CM6
“1” ←→ “0”
“_{1C” ←}^M“06_→^{C” ←M7→} _{“1”}
“_0”
High-speed mode
(f(φ) = 4 MHz)
CM7 = 0
CM6 = 0
CM5 = 0 (8 MHz oscillating)
CM4 = 1 (32 kHz oscillating)
Low-speed mode
(f(φ)=16 kHz)
CM7 = 1
CM6 = 0
CM5 = 0 (8 MHz oscillating)
CM4 = 1 (32 kHz oscillating)
b7 b4
CPU mode register
(CPUM : address 003B16)
Low-speed mode
(f(φ)=16 kHz)
CM7 = 1
CM6 = 0
CM5 = 1 (8 MHz stopped)
CM4 = 1 (32 kHz oscillating)
CM4 : Port Xc switch bit
0 : I/O port function (stop oscillating)
1 : XCIN-XCOUT oscillating function
CM5 : Main clock (XIN- XOUT) stop bit
0 : Operating
1 : Stopped
CM7, CM6: Main clock division ratio selection bit
b7 b6
0 0 : φ = f(XIN)/2 ( High-speed mode)
0 1 : φ = f(XIN)/8 (Middle-speed mode)
1 0 : φ = f(XCIN)/2 (Low-speed mode)
1 1 : Not available
Notes 1 : Switch the mode by the allows shown between the mode blocks. (Do not switch between the modes directly without an allow.)
2 : The all modes can be switched to the stop mode or the wait mode and return to the source mode when the stop mode or the wait mode is
ended.
3 : Timer operates in the wait mode.
4 : When bit 0 of MISRG is “0” and the stop mode is ended, a delay of approximately 1 ms occurs by connecting timer 1 in middle/high-speed
mode.
5 : When bit 0 of MISRG is “0” and the stop mode is ended, the following is performed.
(1) After the clock is restarted, a delay of approximately 256 ms occurs in low-speed mode if Timer 12 count source selection bit is “0”.
(2) After the clock is restarted, a delay of approximately 16 ms occurs in low-speed mode if Timer 12 count source selection bit is “1”.
6 : Wait until oscillation stabilizes after oscillating the main clock XIN before the switching from the low-speed mode to middle/high-speed
mode.
7 : The example assumes that 8 MHz is being applied to the XIN pin and 32 kHz to the XCIN pin. φ indicates the internal clock.
Fig. 43 State transitions of system clock
37