Notes On Rewriting Port Mode Registers - Hitachi H8/3827R Series Hardware Manual

3.4.2

Notes on Rewriting Port Mode Registers

When a port mode register is rewritten to switch the functions of external interrupt pins, the
following points should be observed.
When an external interrupt pin function is switched by rewriting the port mode register that
controls pins IRQ to IRQ
4
the pin function is switched, even if no valid interrupt is input at the pin. Be sure to clear the
interrupt request flag to 0 after switching pin functions. Table 3.5 shows the conditions under
which interrupt request flags are set to 1 in this way.
Table 3.5 Conditions under which Interrupt Request Flag is Set to 1
Interrupt Request
Flags Set to 1
IRR1 IRRI4
IRRI3
IRRI2
IRRI1
IRRI0
IWPR IWPF7
IWPF6
IWPF5
IWPF4
IWPF3
IWPF2
IWPF1
IWPF0
, WKP to WKP
0 7 0
Conditions
When PMR1 bit IRQ4 is changed from 0 to 1 while pin IRQ
bit IEG4 = 0.
When PMR1 bit IRQ4 is changed from 1 to 0 while pin IRQ
bit IEG4 = 1.
When PMR1 bit IRQ3 is changed from 0 to 1 while pin IRQ
bit IEG3 = 0.
When PMR1 bit IRQ3 is changed from 1 to 0 while pin IRQ
bit IEG3 = 1.
When PMR1 bit IRQ2 is changed from 0 to 1 while pin IRQ
bit IEG2 = 0.
When PMR1 bit IRQ2 is changed from 1 to 0 while pin IRQ
bit IEG2 = 1.
When PMR1 bit IRQ1 is changed from 0 to 1 while pin IRQ
bit IEG1 = 0.
When PMR1 bit IRQ1 is changed from 1 to 0 while pin IRQ
bit IEG1 = 1.
When PMR3 bit IRQ0 is changed from 0 to 1 while pin IRQ
bit IEG0 = 0.
When PMR3 bit IRQ0 is changed from 1 to 0 while pin IRQ
bit IEG0 = 1.
When PMR5 bit WKP7 is changed from 0 to 1 while pin WKP
When PMR5 bit WKP6 is changed from 0 to 1 while pin WKP
When PMR5 bit WKP5 is changed from 0 to 1 while pin WKP
When PMR5 bit WKP4 is changed from 0 to 1 while pin WKP
When PMR5 bit WKP3 is changed from 0 to 1 while pin WKP
When PMR5 bit WKP2 is changed from 0 to 1 while pin WKP
When PMR5 bit WKP1 is changed from 0 to 1 while pin WKP
When PMR5 bit WKP0 is changed from 0 to 1 while pin WKP
, the interrupt request flag may be set to 1 at the time
is low and IEGR
4
is low and IEGR
4
is low and IEGR
3
is low and IEGR
3
is low and IEGR
2
is low and IEGR
2
is low and IEGR
1
is low and IEGR
1
is low and IEGR
0
is low and IEGR
0
is low.
7
is low.
6
is low.
5
is low.
4
is low.
3
is low.
2
is low.
1
is low.
0
85