IDT72V51546L6BB8 IDT, Integrated Device Technology Inc, IDT72V51546L6BB8 Datasheet - Page 28

• Manufacturer Part Number: IDT72V51546L6BB8
• Description: IC FLOW CTRL MULTI QUEUE 256-BGA
• Manufacturer: IDT, Integrated Device Technology Inc

Specifications of IDT72V51546L6BB8

• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 72V51546L6BB8

on the PAEn/PRn bus can change every RCLK cycle. Also, data can be read
out of a queue on the same RCLK rising edge that a quadrant is being selected,
the only restriction being that a read queue selection and PAEn/PRn quadrant
selection cannot be made on the same RCLK cycle.
status output on PAE[0:7] constantly.
device the PAEn/PRn busses of all devices are connected together, when
switching between quadrants of different devices the user must utilize the 3 most
significant bits of the RDADD address bus (as well as the 2 LSB’s). These 3
MSB’s correspond to the device ID inputs, which are the static inputs, ID0, ID1
& ID2.
for timing information. Also refer to Table 2, Read Address Bus, RDADD.
PAEn – POLLED BUS
(looped) mode. In polled mode the PAEn/PRn bus automatically cycles
through the 4 quadrants within the device regardless of how many queues
have been setup in the part. Every rising edge of the RCLK causes the next
quadrant to be loaded on the PAEn/PRn bus. The device configured as the
master (MAST input tied HIGH), will take control of the PAEn/PRn after MRS
goes LOW. For the whole RCLK cycle that the first quadrant is on PAEn/PRn
the ESYNC (PAEn/PRn bus sync) output will be HIGH, for all other quadrants,
this ESYNC output will be LOW. This ESYNC output provides the user with
a mark with which they can synchronize to the PAEn/PRn bus, ESYNC is
IDT72V51546/72V51556 3.3V, MULTI-QUEUE FLOW-CONTROL DEVICES
(32 QUEUES) 36 BIT WIDE CONFIGURATION 1,179,648 and 2,359,296 bits
Quadrants can be selected on consecutive clock cycles, that is the quadrant
If 8 or less queues are setup then queues, Queue[0:7] have their PAE/PR
When the multi-queue devices are connected in expansion of more than one
Please refer to Figure 26, PAE n/ PR n - Direct Mode Quadrant Selection
If FM is HIGH at master reset then the PAEn/PRn bus operates in Polled
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always HIGH for the RCLK cycle that the first quadrant of a device is present
on the PAEn/PRn bus.
set as the Master, MAST input tied HIGH, all other devices will have MAST
tied LOW. The master device is the first device to take control of the PAEn/PRn
bus and will place its first quadrant on the bus on the rising edge of RCLK after
the MRS input goes LOW. For the next 3 RCLK cycles the master device will
maintain control of the PAEn/PRn bus and cycle its quadrants through it, all other
devices hold their PAEn/PRn outputs in High-Impedance. When the master
device has cycled all of its quadrants it passes a token to the next device in the
chain and that device assumes control of the PAEn/PRn bus and then cycles
its quadrants and so on, the PAEn/PRn bus control token being passed on from
device to device. This token passing is done via the EXO outputs and EXI inputs
of the devices (“PAE Expansion Out” and “PAE Expansion In”). The EXO
output of the master device connects to the EXI of the second device in the chain
and the EXO of the second connects to the EXI of the third and so on. The final
device in a chain has its EXO connected to the EXI of the first device, so that
once the PAEn/PRn bus has cycled through all quadrants of all devices, control
of the PAEn/PRn will pass to the master device again and so on. The ESYNC
of each respective device will operate independently and simply indicate when
that respective device has taken control of the bus and is placing its first quadrant
on to the PAEn/PRn bus.
the EXO output of the same device. In single device mode a token is still required
to be passed into the device for accessing the PAEn bus.
information.
When devices are connected in expansion mode, only one device will be
Please refer to Figure 31, PAE n/ PR n Bus – Polled Mode for timing
When operating in single device mode the EXI input must be connected to
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TEMPERATURE RANGES