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Brf (branch far) – Echelon Neuron User Manual

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BRF (Branch Far)

The BRF instruction performs an unconditional branch. The BRF instruction

uses the relative addressing mode. The BRF instruction branches to a specified

absolute address. The address expression can resolve at link time to any value

within the 64 KB address space.
The Neuron Assembler also supports the use of a label for the address

expression; manual calculation of the displacement value is not required.
See also BR (Branch) and SBR (Short Branch) for shorter unconditional

branches.
The BRF instruction applies to Series 3100, 5000, and 6000 devices.

Syntax:
The BRF instruction requires a single operand to specify the address or label:

BRF address

BRF label

Table 18 describes the attributes of the BRF instruction.

Table 18. BRF Instruction

Instruction

Hexadecimal

Opcode

Instruction

Size (Bytes)

CPU Cycles

Required

Affect on

Carry Flag

BRF

75

3

4

None


Example:
The following example uses the BRF instruction to branch into a library

function, whose address is unknown until the program is compiled and linked.

brf LibRoutine ;

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Neuron Assembly Language Instruction Statements