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SBR (Short Branch)

The SBR instruction performs an unconditional branch. The SBR instruction

uses the (short) relative addressing mode. The SBR instruction branches

forward with an unsigned relative displacement of 1 to 16 bytes. The

displacement expression must resolve at link time to a value in the range 0 to 15

(one less than the actual displacement because the displacement calculation

includes the size of the SBR operation itself).

Note that the minimum short branch (forward one byte), SBR *+1, is equivalent

to a no operation (NOP) instruction.

The Neuron Assembler also supports the use of a label for the displacement

expression; manual calculation of the displacement value is not required.

See also BR (Branch) and BRF (Branch Far) for longer unconditional branches.

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

Syntax:

The SBR instruction requires a single operand to specify the displacement or

label:

SBR displacement

SBR label

Table 49 describes the attributes of the SBR instruction. In the table, the

asterisk (*) specifies the current value of the instruction pointer (IP).

Table 49. SBR Instruction

Instruction Hexadecimal

Opcode

Instruction

Size (Bytes)

CPU Cycles

Required

Affect on

Carry Flag

SBR *+1 20 1 1 None

SBR *+2 21 1 1 None

SBR *+3 22 1 1 None

SBR *+4 23 1 1 None

SBR *+5 24 1 1 None

SBR *+6 25 1 1 None

SBR *+7 26 1 1 None

SBR *+8 27 1 1 None

SBR *+9 28 1 1 None

Neuron Assembly Language Reference 115

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