**Operation:**

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0 - Destination (base 10) - X -->; Destination

**Assembler Syntax:** NBCD <ea>

**Attributes:** Size = (Byte)

**Description:**Subtracts the source operand and the extend bit from

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zero. The operation is performed using binary coded decimal

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arithmetic. The packed BCD result is saved in the destination

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location. This instruction produces the tens complement of

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the destination if the extend bit is zero, or the nines

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complement if the extend bit is one. This operation is a byte

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operation only.

**Condition Codes:**

\c24242

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X Set the same as the carry bit.

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N Undefined.

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Z Cleared if the result is nonzero. Unchanged otherwise.

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V Undefined.

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C Set if a decimal carry was generated. Cleared otherwise.

Note: Normally the Z condition code bit is set via programming before

the start of an operation. This allows successful tests for zero results

upon completion of multiple-precision operations.