Texas Instruments MSP50C614 manual Conditionals

Models: MSP50C614

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Conditionals

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.

 

 

 

 

'NOT'³

'NOT' ³

 

 

 

Alternate²

condition

STAT register

Arithmetic/Logic

Condition

condition

alternate²

bit settings

Condition

mnemonic

mnemonic

mnemonic

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

Rx carry flag

RCF

 

RNCF

 

 

 

 

 

 

 

RZF = 0 & RCF = 1

Rx above (unsigned)

RA

RNBE

RNA

RBE

 

 

 

 

 

 

RZF = 1

Rx 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

²Alternate mnemonics are provided to help program readability. They generate the same opcodes as the associated condition. ³ Status Register (STAT) bit settings are inverted for NOT conditions.

§ Hardware lines used for I/O expansion design. These lines are PA0 and PA1.

Assembly Language Instructions

4-69

Page 161
Image 161
Texas Instruments MSP50C614 manual Conditionals