6.42

21

IDT70V35/34S/L (IDT70V25/24S/L)

High-Speed 3.3V 8/4K x 18 (8/4K x 16) Dual-Port Static RAM

Industrial and Commercial Temperature Ranges

NOTES:

1. Assumes

2. If

3. If

Left Port

Right Port

Function

R/

(4)

R/

(4)

LL

X

XXX

X

X

Set Right

XXX

X

X

X

L

L

Reset Right

XXX

X

LL

X

XSet Left

XL

L

X

X

X

X

X

Reset Left

5624 tbl 15

Truth Table IV — Address BUSY

Arbitration

NOTES:

1. Pins

IDT70V35/34 (IDT70V25/24) are push pull, not open drain outputs. On slaves the

BUSY input internally inhibits writes.

3. Writes to the left port are internally ignored when

ignored when

Inputs

Outputs

Function

(4)

X

X

NO MATCH

HHNormal

H

X

MATCH

H

H

Normal

X

H

MATCH

H

H

Normal

LL

MATCH

5624 tbl 16

NOTES:

1. This table denotes a sequence of events for only one of the eight semaphores on the IDT70V35/34 (IDT70V25/24).

3.

Functions

Status

No Action

1

1

Semaphore free

Left Port Writes "0" to Semaphore

0

1

Left port has semaphore token

Right Port Writes "0" to Semaphore

0

1

No change. Right side has no write access to semaphore

Left Port Writes "1" to Semaphore

1

0

Right port obtains semaphore token

Left Port Writes "0" to Semaphore

1

0

No change. Left port has no write access to semaphore

Right Port Writes "1" to Semaphore

0

1

Left port obtains semaphore token

Left Port Writes "1" to Semaphore

1

1

Semaphore free

Right Port Writes "0" to Semaphore

1

0

Right port has semaphore token

Right Port Writes "1" to Semaphore

1

1

Semaphore free

Left Port Writes "0" to Semaphore

0

1

Left port has semaphore token

Left Port Writes "1" to Semaphore

1

1

Semaphore free

5624 tbl 17