Cypress CY7C0833AV Retransmit, Mask Reset Operation, Mask Readback Operation, Counting by Two

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CY7C0837AV, CY7C0830AV CY7C0831AV, CY7C0832AV CY7C0832BV, CY7C0833AV

Retransmit

Retransmit is a feature that allows the Read of a block of memory more than once without the need to reload the initial address. This eliminates the need for external logic to store and route data. It also reduces the complexity of the system design and saves board space. An internal mirror register is used to store the initially loaded address counter value. When the counter unmasked portion reaches its maximum value set by the mask register, it wraps back to the initial value stored in this mirror register. If the counter is continuously configured in increment mode, it increments again to its maximum value and wraps back to the value initially stored into the mirror register. Thus, the repeated access of the same data is allowed without the need for any external logic.

Mask Reset Operation

The mask register is reset to all ‘1s,’ which unmasks every bit of the counter. Master reset (MRST) also resets the mask register to all ‘1s’.

Mask Readback Operation

The internal value of the mask register can be read out on the address lines. Readback is pipelined; the address is valid tCM2 after the next rising edge of the port’s clock. If mask readback occurs while the port is enabled (CE0 LOW and CE1 HIGH), the data lines (DQs) is three-stated. Figure 3 on page 9 shows a block diagram of the operation.

Counting by Two

When the least significant bit of the mask register is ‘0,’ the counter increments by two. This may be used to connect the x18 devices as a 36-bit single port SRAM in which the counter of one port counts even addresses and the counter of the other port counts odd addresses. This even-odd address scheme stores one half of the 36-bit data in even memory locations, and the other half in odd memory locations.

Mask Load Operation

The mask register is loaded with the address value presented at the address lines. Not all values permit correct increment opera- tions. Permitted values are of the form 2n – 1 or 2n – 2. From the most significant bit to the least significant bit, permitted values have zero or more ‘0s,’ one or more ‘1s,’ or one ‘0.’ Thus 3FFFF, 003FE, and 00001 are permitted values, but 3F0FF, 003FC, and 00000 are not.

Document #: 38-06059 Rev. *S

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Contents Features Functional DescriptionLogic Block Diagram TrueRAM Array Mirror RegPin Configurations DQ9 L DQ9 RCE1L Pin Definitions Byte Select OperationMaster Reset Mailbox InterruptsAddress Counter and Mask Register Operations Interrupt Operation Example 2, 12, 13, 14, 15Counter Reset Operation Counter Load OperationCounter Increment Operation Counter Hold OperationMask Reset Operation RetransmitMask Readback Operation Counting by TwoCnten ADS Cntrst Mrst CLKPerforming a TAP Reset Ieee 1149.1 Serial Boundary Scan JtagPerforming a Pause/Restart Boundary Scan Hierarchy for 9-Mbit DeviceInstruction Code Description Scan Registers Sizes Register Name Bit SizeInstruction Identification Codes Electrical Characteristics Maximum RatingsOperating Range CapacitanceSwitching Characteristics Delays Master Reset TimingJtag Timing and Switching Waveforms Switching Waveforms Read Cycle12, 30, 31, 32Bank Select Read34 Read-to-Write-to-Read OE Controlled33, 36, 38 Write with Address Counter Advance39 Readback State of Address Counter or Mask Register43, 44, 45 Lport RportCounter Interrupt and Retransmit 15, 42, 50, 51, 52 Outputs Disabled DeselectedWrite ReadOrdering Information 512K × 18 9M 3.3V Synchronous CY7C0833AV Dual-Port Sram128K × 18 2M 3.3V Synchronous CY7C0831AV Dual-Port Sram 64K × 18 1M 3.3V Synchronous CY7C0830AV Dual-Port SramPackage Diagrams 32K × 18 512K 3.3V Synchronous CY7C0837AV Dual-Port SramPin Thin Quad Flatpack 14 x 14 x 1.4 mm Document History USB Sales, Solutions, and Legal InformationWorldwide Sales and Design Support Products PSoC Solutions

CY7C0837AV, CY7C0833AV, CY7C0831AV, CY7C0830AV, CY7C0832AV specifications

Cypress Semiconductor, a leader in innovative semiconductor solutions, has developed a range of high-performance SRAM (Static Random Access Memory) products, including the CY7C0837AV, CY7C0833AV, CY7C0831AV, CY7C0830AV, and CY7C0832AV. These devices cater to various applications requiring fast, reliable memory storage.

One of the main features of these SRAMs is their speed. They offer fast access times, which range from 10 to 15 nanoseconds. This rapid access is critical for applications where speed is essential, such as high-speed networking and telecommunications equipment, automotive systems, and industrial controls. The CY7C0837AV, for instance, boasts a 1 Mbit memory capacity, making it suitable for applications requiring a larger data buffer.

Another notable feature of these devices is their low power consumption. The SRAMs are designed to operate at low voltages, typically around 3.3V, which greatly reduces the overall power requirements. This characteristic is particularly advantageous for battery-operated devices and portable electronics, as it extends battery life and improves energy efficiency.

Cypress's SRAM offerings incorporate advanced technologies like asynchronous read and write operations, which enable users to access memory without the need for a clock signal. This asynchronous nature allows for simpler system designs and integration, significantly reducing component count and complexity.

In terms of packaging, these SRAMs are available in various formats, including standard DIP and surface-mount options, facilitating easy integration into a range of printed circuit boards. Their footprint and compatibility with existing designs ensure they can be utilized in both new developments and legacy system enhancements.

The CY7C0837AV, CY7C0833AV, CY7C0831AV, CY7C0830AV, and CY7C0832AV also support burst mode operations, allowing for faster sequential data access. This feature enhances performance in applications that require continuous data streams, such as video processing and signal processing tasks.

In summary, the Cypress CY7C0837AV, CY7C0833AV, CY7C0831AV, CY7C0830AV, and CY7C0832AV SRAMs provide a combination of high speed, low power consumption, and versatile packaging options. Their advanced technologies and characteristics make them ideal for a wide range of applications, from automotive to industrial systems, solidifying their position as reliable memory solutions in the semiconductor market.
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