Specifications

ManualsBrandsVax ManualsHousehold AppliancesV-092

5.3

.BIT

BlIT

ACCELERATOR

5.3.1

FUNCTIONAL

DESCRIPTION

The

Blit

Bit

Accelerator

(BBA)

is

used

to

move

data

to

and

from

the

Display

Processor

Screen

memor~

at

hi~h

speed

independant

of

the

Display

Processor

CPU.

The

BBA

recieves

command

packets

from

the

Displa~

processor,

and

can

~odifY,manipulate

and

move

data

for

the

purpose

of

Guickly

chanSins

visuall~

displa~ed

information.

From

a

functional

viewpoint,

the

BBA

is

divided

into

two

sections.

One

seeton

-interpets

commands,computes

addresses,

and

provides

control

and

execution

of

alsorithms.

The

second

section

is

used

to

process

bit

data.

The

followinS

instructions

are

suPPorted

b~

the.BBA

firmware

A.

COpy

AREA

B.

PRINT

TEXT

C.

VECTOR

D.

HAlFTON~

For

a

complete

description

of

these

instructions,

refer

to

the

WORKSTATION

GRAPHIC

ARCHITECTURE

Vl.0

,HANK

lEVY

MARCH

1,

1983

5.3.2

BLOCK

DIAGRAM

to/from

BBA

address

bus

23

bits

DPM

><-------------------------------

I

V

ISCRATCHI

I

PAD

,

,

MEMORY'

I

ADDRESS

,

PATH

1 I

1------------------------

I .

to/from

V

BBA

data

bus

16

bits

DPM

><---------------------------

I

DATA

PATH

I

to

all

blocks

I

MICRO

CODE

I

56

bits

I

}~

lk.