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12 conditionals – Texas Instruments MSP50C614 User Manual

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Conditionals

4-69

Assembly Language Instructions

4.12 Conditionals

The condition bits in the status register (STAT) are used to modify program
control through conditional branches and calls. Various combinations of bits
are available to provide a rich set of conditional operations. These condition
bits can also be used in Boolean operations to set the test flags TF1 and TF2
in the status register.

STAT register
bit settings

Arithmetic/Logic
Condition

Condition
mnemonic

Alternate

mnemonic

’NOT’

condition
mnemonic

’NOT’

condition
alternate

mnemonic

ZF = 1

Zero flag

ZF

NZF

SF = 1

Sign flag

SF

NSF

CF = 1

Carry flag

CF

NCF

ZF = 0 & CF = 0

Below (unsigned)

B

NAE

NB

AE

ZF = 0 & CF = 1

Above (unsigned)

A

NBE

NA

BE

ZF = 1 & SF = 0

Greater (signed)

G

NLE

NG

LE

ZF = 1 & OF = 0

Equal

E

NE

OF = 1

Overflow flag

OF

NOF

ZF = 0 & SF = 1

Less (signed)

L

NGE

NL

GE

RCF = 1

R

x carry flag

RCF

RNCF

RZF = 0 & RCF = 1

R

x above (unsigned)

RA

RNBE

RNA

RBE

RZF = 1

R

x equal

RE

RZ

RNE

RNZ

TF1 = 1

Test flag 1

TF1

NTF1

TF2 = 1

Test flag 2

TF2

NTF2

TAG = 1

Memory tag

TAG

NTAG

IN1

§

Input line 1

IN1

NIN1

IN2

§

Input line 2

IN2

NIN2

XZF = 1

Transfer zero flag

XZF

XNZF

XSF = 1

Transfer sign flag

XSF

XNSF

XZF = 0 & XSF = 0

Transfer greater (signed)

XG

XNLE

XNG

XLE

† Alternate mnemonics are provided to help program readability. They generate the same opcodes as the associated condition.
‡ Status Register (STAT) bit settings are inverted for NOT conditions.
§ Hardware lines used for I/O expansion design. These lines are PA0 and PA1.