Compare bits in assembly

assembly 8051 microprocessors
Baran picture Baran · Apr 28, 2011 · Viewed 7.1k times · Source

How can I compare two bits if they are equal or not in 8051? I need to jump if two bits are equal. I have a value in a register and I am searching if this value is equal another constant value. Example: I have "EDh" value and I have another value in R0 register.

Answer

Oliver Charlesworth picture Oliver Charlesworth · Apr 28, 2011

To compare a register and an immediate (a constant), and then conditionally jump, you can use the CJNE instruction.

Related questions

Writing a delay subroutine?

I need to write a delay subroutine. It should delay about 1 second. It has to be for 8051 environment, DS89C430 micrcontroller ( 11.0592 MHz XTAL). How can I write this subroutine? Delay1sec: ... .... ... .... ...

Read More
What is JB used for here?

I'm trying to understand some example asm that came with a development board (XL400), with a view to converting it to C. The asm code is included below, unfortunately the documentation, such as it is, is translated very badly from …

Read More
ADDC versus ADD

I'm trying to figure out the difference between ADDC and ADD instructions for 8051 microcontrollers. Description: ADD and ADDC both add the value operand to the value of the Accumulator, leaving the resulting value in the Accumulator. The value operand is …

Read More