IDT72T51543, IDT72T51546, IDT72T51553

The IDT72T51543/72T51553 multi-queue flow-control devices are single chip within which anywhere between 1 and 32 discrete FIFO queues can be setup. All queues within the device have a common data input bus, (write port) and a common data output bus, (read port). Data written into the write port is directed to a respective queue via an internal de-multiplex operation, addressed by the user. Data read from the read port is accessed from a respective queue via an internal multiplex operation, addressed by the user. Data writes and reads can be performed at high speeds up to 200MHz, with access times of 3.6ns. Data write and read operations are totally independent of each other, a queue maybe selected on the write port and a different queue on the read port or both ports may select the same queue simultaneously.

The device provides Full flag and Output Valid flag status for the queue selected for write and read operations respectively. Also a Programmable Almost Full and Programmable Almost Empty flag for each queue is provided. Two 8 bit programmable flag busses are available, providing status of queues not selected for write or read operations. When 8 or less queues are configured in the device these flag busses provide an individual flag per queue, when more than 8 queues are used, either a Polled or Direct mode of bus operation provides the flag busses with all queues status.

Bus Matching is available on this device, either port can be 9 bits or 18 bits wide. When Bus Matching is used the device ensures the logical transfer of data throughput in a Little Endian manner.

The user has full flexibility configuring queues within the device, being able\ to program the total number of queues between 1 and 32, the individual queue depths being independent of each other. The programmable flag positions are also user programmable. All programming is done via a dedicated serial port. If the user does not wish to program the multi-queue device, a default option is available that configures the device in a predetermined manner.

Both Master Reset and Partial Reset pins are provided on this device. A Master Reset latches in all configuration setup pins and must be performed before programming of the device can take place. A Partial Reset will reset the read and write pointers of an individual queue, provided that the queue is selected on both the write port and read port at the time of partial reset.

Echo Read Enable, EREN and Echo Read Clock, ERCLK outputs are provided. These are outputs from the read port of the queue that are required for high speed data communication, to provide tighter synchronization between the data being transmitted from the Qn outputs and the data being received by the input device. Data read from the read port is available on the output bus with respect to EREN and ERCLK, this is very useful when data is being read at high speed.

The multi-queue flow-control device has the capability of operating its IO in either 2.5V LVTTL, 1.5V HSTL or 1.8V eHSTL mode. The type of IO is selected via the IOSEL input. The core supply voltage (VCC) to the multi-queue is always 2.5V, however the output levels can be set independently via a separate supply, VDDQ.

The devices also provide additional power savings via a Power Down Input. This input disables the write port data inputs when no write operations are required.

A JTAG test port is provided, here the multi-queue device has a fully functional Boundary Scan feature, compliant with IEEE 1149.1 Standard Test Access Port\ and Boundary Scan Architecture.

See Figure 1, Multi-Queue Flow-Control Device Block Diagram for an outline of the functional blocks within the device.

The IDT72T51546/72T51556 multi-queue flow-control devices is a single chip within which anywhere between 1 and 32 discrete FIFO queues can be setup. All queues within the device have a common data input bus, (write port) and a common data output bus, (read port). Data written into the write port is directed to a respective queue via an internal de-multiplex operation, addressed by the user. Data read from the read port is accessed from a respective queue via an internal multiplex operation, addressed by the user. Data writes and reads can be performed at high speeds up to 200MHz, with access times of 3.6ns. Data write and read operations are totally independent of each other, a queue maybe selected on the write port and a different queue on the read port or both ports may select the same queue simultaneously.

The device provides Full flag and Output Valid flag status for the queue selected for write and read operations respectively. Also a Programmable Almost Full and Programmable Almost Empty flag for each queue is provided. Two 8 bit programmable flag busses are available, providing status of queues not selected for write or read operations. When 8 or less queues are configured in the device these flag busses provide an individual flag per queue, when more than 8 queues are used, either a Polled or Direct mode of bus operation provides the flag busses with all queues status.

Bus Matching is available on this device, either port can be 9 bits, 18 bits or 36 bits wide provided that at least one port is 36 bits wide. When Bus Matching is used the device ensures the logical transfer of data throughput in a Little Endian manner.

A packet mode of operation is also provided when the device is configured for 36 bit input and 36 bit output port sizes. The Packet mode provides the user with a flag output indicating when at least one (or more) packets of data within a queue is available for reading. The Packet Ready provides the user with a means by which to mark the start and end of packets of data being passed through the queues. The multi-queue device then provides the user with an internally generated packet ready status per queue.

The user has full flexibility configuring queues within the device, being able to program the total number of queues between 1 and 32, the individual queue depths being independent of each other. The programmable flag positions are also user programmable. All programming is done via a dedicated serial port. If the user does not wish to program the multi-queue device, a default option is available that configures the device in a predetermined manner.

Both Master Reset and Partial Reset pins are provided on this device. A Master Reset latches in all configuration setup pins and must be performed before programming of the device can take place. A Partial Reset will reset the read and write pointers of an individual queue, provided that the queue is selected on both the write port and read port at the time of partial reset.

Echo Read Enable, EREN and Echo Read Clock, ERCLK outputs are provided. These are outputs from the read port of the Queue that are required for high speed data communication, to provide tighter synchronization between the data being transmitted from the Qn outputs and the data being received by the input device. Data read from the read port is available on the output bus with respect to EREN and ERCLK, this is very useful when data is being read at high speed.

The multi-queue flow-control device has the capability of operating its IO in either 2.5V LVTTL, 1.5V HSTL or 1.8V eHSTL mode. The type of IO is selected via the IOSEL input. The core supply voltage (VCC) to the multi-queue is always 2.5V, however the output levels can be set independently via a separate supply, VDDQ.

The devices also provide additional power savings via a Power Down Input. This input disables the write port data inputs when no write operations are required.

A JTAG test port is provided, here the multi-queue flow-control device has a fully functional Boundary Scan feature, compliant with IEEE 1149.1 Standard Test Access Port and Boundary Scan Architecture.

See Figure 1, Multi-Queue Flow-Control Device Block Diagram for an outline of the functional blocks within the device.

The IDT72T51543/72T51553 multi-queue flow-control devices are single chip within which anywhere between 1 and 32 discrete FIFO queues can be setup. All queues within the device have a common data input bus, (write port) and a common data output bus, (read port). Data written into the write port is directed to a respective queue via an internal de-multiplex operation, addressed by the user. Data read from the read port is accessed from a respective queue via an internal multiplex operation, addressed by the user. Data writes and reads can be performed at high speeds up to 200MHz, with access times of 3.6ns. Data write and read operations are totally independent of each other, a queue maybe selected on the write port and a different queue on the read port or both ports may select the same queue simultaneously.

The device provides Full flag and Output Valid flag status for the queue selected for write and read operations respectively. Also a Programmable Almost Full and Programmable Almost Empty flag for each queue is provided. Two 8 bit programmable flag busses are available, providing status of queues not selected for write or read operations. When 8 or less queues are configured in the device these flag busses provide an individual flag per queue, when more than 8 queues are used, either a Polled or Direct mode of bus operation provides the flag busses with all queues status.

Bus Matching is available on this device, either port can be 9 bits or 18 bits wide. When Bus Matching is used the device ensures the logical transfer of data throughput in a Little Endian manner.

The user has full flexibility configuring queues within the device, being able\ to program the total number of queues between 1 and 32, the individual queue depths being independent of each other. The programmable flag positions are also user programmable. All programming is done via a dedicated serial port. If the user does not wish to program the multi-queue device, a default option is available that configures the device in a predetermined manner.

Both Master Reset and Partial Reset pins are provided on this device. A Master Reset latches in all configuration setup pins and must be performed before programming of the device can take place. A Partial Reset will reset the read and write pointers of an individual queue, provided that the queue is selected on both the write port and read port at the time of partial reset.

Echo Read Enable, EREN and Echo Read Clock, ERCLK outputs are provided. These are outputs from the read port of the queue that are required for high speed data communication, to provide tighter synchronization between the data being transmitted from the Qn outputs and the data being received by the input device. Data read from the read port is available on the output bus with respect to EREN and ERCLK, this is very useful when data is being read at high speed.

The multi-queue flow-control device has the capability of operating its IO in either 2.5V LVTTL, 1.5V HSTL or 1.8V eHSTL mode. The type of IO is selected via the IOSEL input. The core supply voltage (VCC) to the multi-queue is always 2.5V, however the output levels can be set independently via a separate supply, VDDQ.

The devices also provide additional power savings via a Power Down Input. This input disables the write port data inputs when no write operations are required.

A JTAG test port is provided, here the multi-queue device has a fully functional Boundary Scan feature, compliant with IEEE 1149.1 Standard Test Access Port\ and Boundary Scan Architecture.

See Figure 1, Multi-Queue Flow-Control Device Block Diagram for an outline of the functional blocks within the device.