MITSUBISHI MICROCOMPUTERS
7477/7478 GROUP
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
<An example of flow for system>
Power on reset
↓
Clock X oscillation
↓
Internal system clock start (X→1/2→ φ)
↓
Program start from RESET vector
Normal program
Operating at f(XIN)
Clock for clock function XC oscillation start (CM4 = 1, CM5 = 1)
↓
←
Latency time for oscillation to stabilize (by program)
Operating at f(XIN)
↓
→
XC clock power down (CM5 : 1 0)
↓
→ →
XC (CM7 : 0 1)
Internal clock φ source switching
X
↓
Clock X halt (XC in operation) (CM6 = 1)
↓
Internal clock halt (WIT instruction)
↓
Timer 4 (clock count) overflow
↓
Internal clock operation start (WIT instruction released)
←
Clock processing routine
Operating at f(XCIN)
Internal clock halt (WIT instruction)
Interrupts from INT0, INT1, CNTR0/CNTR1, timer 1, timer 2, timer 3, timer 4, serial I/O, key on wake up
↓
Internal clock operation start (WIT instruction released)
↓
Program start from interrupt vector
↓
Clock X oscillation start (CM6 = 0)
↓
←
Latency time for oscillation to stabilize (by program)
Operating at f(XCIN)
↓
→
→
Internal clock φ source switching (XC X) (CM7 : 1 0)
→
Normal program
Operating at f(XIN)
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MITSUBISHI [ Mitsubishi Group ]
