Linear Burst Address Table Mode = GND | Cypress CY7C1338G manual

CY7C1338G

Single Write Accesses Initiated by ADSP

This access is initiated when the following conditions are satisfied at clock rise: (1) CE1, CE2, CE3 are all asserted active, and (2) ADSP is asserted LOW. The addresses presented are loaded into the address register and the burst inputs (GW, BWE, and BW[A:D])are ignored during this first clock cycle. If the write inputs are asserted active (see Write Cycle Descriptions table for appropriate states that indicate a write) on the next clock rise, the appropriate data will be latched and written into the device. Byte writes are allowed. During byte writes, BWA controls DQA and BWB controls DQB. BWC controls DQC, and BWD controls DQD. All I/Os are tri-stated during a byte write.Since this is a common I/O device, the asynchronous OE input signal must be deasserted and the I/Os must be tri-stated prior to the presentation of data to DQs. As a safety precaution, the data lines are tri-stated once a write cycle is detected, regardless of the state of OE.

Single Write Accesses Initiated by ADSC

This write access is initiated when the following conditions are satisfied at clock rise: (1) CE1, CE2, and CE3 are all asserted active, (2) ADSC is asserted LOW, (3) ADSP is deasserted HIGH, and (4) the write input signals (GW, BWE, and BW[A:D]) indicate a write access. ADSC is ignored if ADSP is active LOW.

The addresses presented are loaded into the address register and the burst counter/control logic and delivered to the memory core. The information presented to DQ[A:D] will be written into the specified address location. Byte writes are allowed. During byte writes, BWA controls DQA, BWB controls DQB, BWC controls DQC, and BWD controls DQD. All I/Os are tri-stated when a write is detected, even a byte write. Since this is a common I/O device, the asynchronous OE input signal must be deasserted and the I/Os must be tri-stated prior to the presentation of data to DQs. As a safety precaution, the data lines are tri-stated once a write cycle is detected, regardless of the state of OE.

Burst Sequences

The CY7C1338G provides an on-chip two-bit wraparound burst counter inside the SRAM. The burst counter is fed by

A[1:0], and can follow either a linear or interleaved burst order. The burst order is determined by the state of the MODE input. A LOW on MODE will select a linear burst sequence. A HIGH on MODE will select an interleaved burst order. Leaving MODE unconnected will cause the device to default to a inter- leaved burst sequence.

Sleep Mode

The ZZ input pin is an asynchronous input. Asserting ZZ places the SRAM in a power conservation “sleep” mode. Two clock cycles are required to enter into or exit from this “sleep” mode. While in this mode, data integrity is guaranteed. Accesses pending when entering the “sleep” mode are not considered valid nor is the completion of the operation guaranteed. The device must be deselected prior to entering the “sleep” mode. CEs, ADSP, and ADSC must remain inactive for the duration of tZZREC after the ZZ input returns LOW.

Interleaved Burst Address Table (MODE = Floating or VDD)

First	Second	Third	Fourth
Address	Address	Address	Address
A1, A0	A1, A0	A1, A0	A1, A0
00	01	10	11
01	00	11	10
10	11	00	01
11	10	01	00