Renesas F-ZTAT H8 Series Hardware Manual page 94

2. CPU
As a result of this operation, bit 0 in PCR3 becomes 0, making P3
and 6 in PCR3 change to 1, so that P3
To avoid this problem, store a copy of the PCR3 data in a work area in memory. Perform the bit
manipulation on the data in the work area, then write this data to PCR3.
[A: Prior to executing BCLR]
MOV. B #3F,
MOV. B R0L,
MOV. B R0L,
P3
7
Input/output Input
Pin state Low
level
PCR3 0
PDR3 1
RAM0 0
[B: BCLR instruction executed]
BCLR #0 ,
[C: After executing BCLR]
MOV. B @RAM0, R0L
MOV. B R0L,
P3
7
Input/output Input
Pin state Low
level
PCR3 0
PDR3 1
RAM0 0
Rev.3.00 Jul. 19, 2007 page 68 of 532
REJ09B0397-0300
and P3
7
R0L The PCR3 value (H'3F) is written to a work area in memory
(RAM0) as well as to PCR3.
@RAM0
@PCR3
P3 P3
6 5
Input Output
High Low
level level
0 1
0 0
0 1
@RAM0 The BCLR instruction is executed designating the PCR3
work area (RAM0).
The work area (RAM0) value is written to PCR3.
@PCR3
P3 P3
6 5
Input Output
High Low
level level
0 1
0 0
0 1
0
change from input pins to output pins.
6
P3 P3
4 3
Output Output
Low Low
level level
1 1
0 0
1 1
P3 P3
4 3
Output Output
Low Low
level level
1 1
0 0
1 1
an input port. However, bits 7
P3 P3
2 1
Output Output
Low Low
level level
1 1
0 0
1 1
P3 P3
2 1
Output Output
Low Low
level level
1 1
0 0
1 1
P3
0
Output
Low
level
1
0
1
P3
0
Output
High
level
0
0
0