Cypress CY7C1338G manual Address Cycle Description Used, CE2 Adsp Adsc ADV Write CLK

CY7C1338G

Truth Table [2, 3, 4, 5, 6]

Address

Cycle Description

Used

CE

1

CE2

CE

3

ZZ

ADSP

ADSC

ADV

WRITE

OE

CLK

DQ

Deselected Cycle, Power-down

None

H

X

X

L

X

L

X

X

X

L-H

Tri-State

Deselected Cycle, Power-down

None

L

L

X

L

L

X

X

X

X

L-H

Tri-State

Deselected Cycle, Power-down

None

L

X

H

L

L

X

X

X

X

L-H

Tri-State

Deselected Cycle, Power-down

None

L

L

X

L

H

L

X

X

X

L-H

Tri-State

Deselected Cycle, Power-down

None

X

X

X

L

H

L

X

X

X

L-H

Tri-State

Sleep Mode, Power-down

None

X

X

X

H

X

X

X

X

X

X

Tri-State

Read Cycle, Begin Burst

External

L

H

L

L

L

X

X

X

L

L-H

Q

Read Cycle, Begin Burst

External

L

H

L

L

L

X

X

X

H

L-H

Tri-State

Write Cycle, Begin Burst

External

L

H

L

L

H

L

X

L

X

L-H

D

Read Cycle, Begin Burst

External

L

H

L

L

H

L

X

H

L

L-H

Q

Read Cycle, Begin Burst

External

L

H

L

L

H

L

X

H

H

L-H

Tri-State

Read Cycle, Continue Burst

Next

X

X

X

L

H

H

L

H

L

L-H

Q

Read Cycle, Continue Burst

Next

X

X

X

L

H

H

L

H

H

L-H

Tri-State

Read Cycle, Continue Burst

Next

H

X

X

L

X

H

L

H

L

L-H

Q

Read Cycle, Continue Burst

Next

H

X

X

L

X

H

L

H

H

L-H

Tri-State

Write Cycle, Continue Burst

Next

X

X

X

L

H

H

L

L

X

L-H

D

Write Cycle, Continue Burst

Next

H

X

X

L

X

H

L

L

X

L-H

D

Read Cycle, Suspend Burst

Current

X

X

X

L

H

H

H

H

L

L-H

Q

Read Cycle, Suspend Burst

Current

X

X

X

L

H

H

H

H

H

L-H

Tri-State

Read Cycle, Suspend Burst

Current

H

X

X

L

X

H

H

H

L

L-H

Q

Read Cycle, Suspend Burst

Current

H

X

X

L

X

H

H

H

H

L-H

Tri-State

Write Cycle, Suspend Burst

Current

X

X

X

L

H

H

H

L

X

L-H

D

Write Cycle, Suspend Burst

Current

H

X

X

L

X

H

H

L

X

L-H

D

Notes:

2.X = “Don't Care.” H = Logic HIGH, L = Logic LOW.

3.WRITE = L when any one or more Byte Write enable signals (BWA, BWB, BWC, BWD) and BWE = L or GW= L. WRITE = H when all Byte write enable signals (BWA, BWB, BWC, BWD), BWE, GW = H.

4.The DQ pins are controlled by the current cycle and the OE signal. OE is asynchronous and is not sampled with the clock.

5.The SRAM always initiates a read cycle when ADSP is asserted, regardless of the state of GW, BWE, or BWX. Writes may occur only on subsequent clocks after the ADSP or with the assertion of ADSC. As a result, OE must be driven HIGH prior to the start of the write cycle to allow the outputs to tri-state. OE is a don't care for the remainder of the write cycle.

6.OE is asynchronous and is not sampled with the clock rise. It is masked internally during write cycles. During a read cycle all data bits are tri-state when OE is inactive or when the device is deselected, and all data bits behave as output when OE is active (LOW).

Document #: 38-05521 Rev. *D Page 6 of 17