HD64F3437TFI16V Renesas Electronics America, HD64F3437TFI16V Datasheet - Page 73

• Manufacturer Part Number: HD64F3437TFI16V
• Description: MCU FLASH 60K 100-TQFP
• Manufacturer: Renesas Electronics America

Specifications of HD64F3437TFI16V

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Before Execution of BCLR Instruction
Input/output
Pin state
DDR
DR
Execution of BCLR Instruction
BCLR
After Execution of BCLR Instruction
Input/output
Pin state
DDR
DR
Explanation: To execute the BCLR instruction, the CPU begins by reading P4DDR. Since
P4DDR is a write-only register, it is read as H'FF, even though its true value is H'3F.
Next the CPU clears bit 0 of the read data, changing the value to H'FE.
Finally, the CPU writes this value (H'FE) back to P4DDR to complete the BCLR instruction.
As a result, P4
are set to 1, making P4
#0, @P4DDR
0
DDR is cleared to 0, making P4
P4
Input
Low
0
1
P4
Output
Low
1
1
7
7
7
and P4
P4
Input
High
0
0
P4
Output
High
1
0
; clear bit 0 in data direction register
6
6
6
output pins.
P4
Output
Low
1
0
P4
Output
Low
1
0
5
5
0
P4
Output
Low
1
0
P4
Output
Low
1
0
an input pin. In addition, P4
4
4
P4
Output
Low
1
0
P4
Output
Low
1
0
3
3
P4
Output
Low
1
0
P4
Output
Low
1
0
2
2
7
DDR and P4
P4
Output
Low
1
0
P4
Output
Low
1
0
1
1
P4
Output
Low
1
0
P4
Input
High
0
0
6
DDR
0
0
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