Write a program in assembly language that will test PIN #0 of PORTA to see if it is at zero or vevolts. Connect an external circuit (taking all precautions to protect the pinfrom excess current/voltage) so that when a circuit is closed the voltage willbe ve volts, or else it is zero volts. The program should print the status ofthe circuit as OPEN or CLOSED.
Solution
bsf STATUS,5 ;to switch the bank if needed
movelw 01h ;setting the bit 0 of portA to be input
movewf TRISA ;address of Port A
bcf STATUS,5 ;switch back
BTFSS PORTA,0
GOTO leb
PRINT the pin is low
leb :
PRINT the pin is high
BTFSS means ‘Do a bit test in the register and bit we specify. If it is set to a 1, then we skip the next instruction.’
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Write a program in assembly language that will test PIN #0 of PORTA to.docx
1. Write a program in assembly language that will test PIN #0 of PORTA to see if it is at zero or
vevolts. Connect an external circuit (taking all precautions to protect the pinfrom excess
current/voltage) so that when a circuit is closed the voltage willbe ve volts, or else it is zero volts.
The program should print the status ofthe circuit as OPEN or CLOSED.
Solution
bsf STATUS,5 ;to switch the bank if needed
movelw 01h ;setting the bit 0 of portA to be input
movewf TRISA ;address of Port A
bcf STATUS,5 ;switch back
BTFSS PORTA,0
GOTO leb
PRINT the pin is low
leb :
PRINT the pin is high
BTFSS means ‘Do a bit test in the register and bit we specify. If it is set to a 1, then we skip
the next instruction.’
