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Texas Instruments MSP50C6xx User Manual

Page 86

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Hardware Initialization States

3-22

Table 3–2. State of the Status Register (17 bit) after RESET Low-to-High

(Bits 5 through 16 are left uninitialized)

Bit

Bit Name

Initialized Value

Description

0

XM

0

Extended sign mode disabled

1

UM

0

Unsigned multiplier mode disabled (allows signed multiplier mode)

2

OM

0

Overflow mode disabled (allows ALU normal mode)

3

FM

0

Shift mode for fractional multiplication disabled (allows unsigned
fractional/integer arithmetic)

4

IM

0

Global interrupt enable bit

5

(reserved)

Reserved for future use

6

XZF

Transfer equal-to-zero status bit

7

XSF

Transfer sign status bit

8

RCF

Auxiliary register carry-out status bit

9

RZF

Auxiliary register equal-to-zero status bit

10

OF

Same state as

Accumulator overflow status bit

11

SF

before RESET

Accumulator sign status bit (extended 17th bit)

12

ZF

Accumulator equal-to-zero status bit (16 bits)

13

CF

Accumulator carry-out status bit (16th ALU bit)

14

TF1

Test flag 1

15

TF2

Test flag 2

16

TAG

Memory tag