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Can I read bit of port register if set port direction register to output?

Latest Updated:02/27/2012

Question:

If I set the Port Direction Register to output and read the corresponding bit of the Port Register, can I read the pin level?

Answer:

No, you cannot. If you set the Port Direction Register to output and read the Port Register, you read the port latch, not the output level of the pin. However, when using UARTi in I2C-bus mode, you can read the pin level, even if the SCL pin is set to output (I value differs depending on each MCU product).
Suitable Products
M32C/8A
M32C/88
M32C/87
M32C/85
M32C/84
M32C/83
M32C/80
M16C/62A
M16C/62A(M16C/62T)
M16C/62M
M16C/62N
M16C/62N(M3062GF8NFP, M3062GF8NGP)
M16C/62P
M16C/63
M16C/64A
M16C/64C
M16C/65
M16C/6C
M16C/6N4, M16C/6N5
M16C/6NK, M16C/6NL, M16C/6NM, M16C/6NN
M16C/5L
M16C/56
M16C/5LD
M16C/56D
M16C/5M
M16C/57
M16C/30P
M16C/29
M16C/28
M16C/26A
M16C/1N