# `dbpl`

[M68K Documentation](https://asm-editor.specy.app/documentation/m68k.md) › [Instructions](https://asm-editor.specy.app/documentation/m68k/instruction.md)

Web page: https://asm-editor.specy.app/documentation/m68k/instruction/dbpl

**Decrement and branch until plus**

Category: Control flow

Tests plus before deciding whether to decrement the counter and branch.

Size .w

## Flags

| Flag | Effect |
| --- | --- |
| X | not changed |
| N | not changed |
| Z | not changed |
| V | not changed |
| C | not changed |

Reads: N

## Forms

- `dbpl Dn, label`

## Operands

- [`Dn`](https://asm-editor.specy.app/documentation/m68k/addressing-mode/direct.md): A data register, `d0` to `d7`.
- [`label`](https://asm-editor.specy.app/documentation/m68k/addressing-mode/effective-address.md): A branch target, written as a label or address. The assembler calculates the relative displacement.

## Description

If the condition is true, execution continues at the next instruction and the counter is unchanged. If it is false, the low word of the data register is decremented; the branch is taken unless that word becomes -1. The upper word is unchanged, and `dbcc` does not change the flags.

The suffix selects the condition. See [condition codes](https://asm-editor.specy.app/documentation/m68k/condition-codes.md). `dbf` and `dbra` always take the decrement path. Starting the low word at N repeats a loop body N + 1 times, up to 65,536 times when it starts at $FFFF.

## Example

```m68k
* --- Loops d0+1 times (decrements THEN tests) ---
move.l #3, d0
move.l #0, d1
loop:
    addq.l #1, d1
    dbra d0, loop ; loop runs 4 times (3, 2, 1, 0)

* --- Stop early when the tested value reaches zero ---
move.l #10, d2
move.l #3, d3
loop2:
    subq.l #1, d3
    tst d3
    dbeq d2, loop2 ; Z set: stop with d3 = 0 and d2 = 8
```