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6.4 External Level Register (ELVR)
6.4 External Level Register (ELVR)

The external level register (ELVR) selects the request detection mode.

■External Level Register (ELVR)
The configuration of the external level register (ELVR) is sho wn below:
The external level register (ELVR) selects the request dete ction mode.
Two bits each are assigned to INT0 to INT3 and defined as shown in Table 6.4-1.
Suppose the level is selected for the requ est de tection mo de. I f inpu t is in the activ e le ve l even
after each EIRR bit is cleared, the corresponding bit is set ag ain.
NMI is always detected at its falling edge (except whe n it stops).
When it stops, it is detected at the L level.
76543210
ELVR
Address:000099
H
LB3 LA3 LB2 LA2 LB1 LA1 LB0 LA0 00000000 R/W
Initial value Access
Table 6.4-1 External Interrupt Request Mode
LBx LAx Request detection mode
00 L level
01H level
1 0 Rising edge
1 1 Falling edge