HD404369 Datasheet, PDF (35/117 Pages) Hitachi Semiconductor – 4-bit HMCS400-Series microcomputer

HD404369 Series
Miscellaneous register (MIS: $00C)
Bit
Initial value
Read/Write
Bit name
3
0
W
MIS3
2
0
W
MIS2
1
0
W
MIS1
0
0
W
MIS0
MIS3 MIS2
Buffer control.
Refer to figure 34.
MIS1
0
0
1
1
MIS0
0
1
0
1
T^*1
t_RC^{* 1} Oscillation Circuit Conditions
0.24414 ms 0.12207 ms External clock input
0.24414 ms^{* 2}
15.625 ms 7.8125 ms Ceramic oscillator
125 ms
62.5 ms
Crystal oscillator
Not used
—
Notes: 1. The values of T and t_RC are applied when a 32.768-kHz crystal oscillator is used.
2. The value is applied only when direct transfer operation is used.
Figure 15 Miscellaneous Register (MIS)
STOP/SBY instruction execution
Subactive mode
MCU internal
processing period
(Set LSON = 0, DTON = 1)
Oscillation
stabilization
time
Active mode
Interrupt strobe
Direct transfer
completion timing
T
t _RC
T_D
T: Interrupt frame length
t_RC: Oscillation stabilization period
t_D: Transition time
Figure 16 Direct Transition Timing
Stop Mode Cancellation by STOPC: The MCU enters active mode from stop mode by inputting STOPC
as well as by RESET. In either case, the MCU starts instruction execution from the starting address
(address 0) of the program. However, the value of the RAM enable flag (RAME: $021, bit 3) differs
between cancellation by STOPC and by RESET. When stop mode is cancelled by RESET, RAME = 0;
when cancelled by STOPC, RAME = 1. RESET can cancel all modes, but STOPC is valid only in stop
mode; STOPC input is ignored in other modes. Therefore, when the program requires to confirm that stop
mode has been cancelled by STOPC (for example, when the RAM contents before entering stop mode is
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