IDT72P51339L6BBI8 IDT, Integrated Device Technology Inc, IDT72P51339L6BBI8 Datasheet - Page 42

• Manufacturer Part Number: IDT72P51339L6BBI8
• Description: IC FLOW CTRL 36BIT 256-BGA
• Manufacturer: IDT, Integrated Device Technology Inc

Specifications of IDT72P51339L6BBI8

• Configuration: Dual
• Density: 576Kb
• Access Time (max): 3.7ns
• Word Size: 36b
• Organization: 2Kx36x8
• Sync/async: Synchronous
• Expandable: Yes
• Bus Direction: Uni-Directional
• Package Type: BGA
• Clock Freq (max): 166MHz
• Supply Current: 150mA
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 256
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 72P51339L6BBI8

FLAG DESCRIPTION
PAFn FLAG BUS OPERATION
trol device can be configured for up to 8 queues, each queue having its own
almost full status. An active queue has its flag status output to the discrete flags,
FF and PAF, on the write port. Queues that are not selected for a write operation
can have their PAF status monitored via the PAFn bus. The PAFn flag bus is
8 bits wide, so that 8 queues at a time can have their status output to the bus.
If 9 or more queues are setup within a device then there are 2 methods by which
the device can share the bus between queues, “Direct” mode and “Polled” mode
depending on the state of the FM (Flag Mode) input during a Master Reset. If
8 or less queues are setup within a device then each will have its own dedicated
output from the bus. If 8 or less queues are setup in single device mode, it is
recommended to configure the PAFn bus to polled mode as it does not require
using the write address (WRADD).
FULL FLAG OPERATION
The FF flag output provides a full status of the queue currently selected on the
write port for write operations. Internally the multi-queue flow-control device
monitors and maintains a status of the full condition of all queues within it, however
only the queue that is selected for write operations has its full status output to the
FF flag. This dedicated flag is often referred to as the “active queue full flag”.
will switch to the new queue and provide the user with the new queue status,
on the 3rd cycle after a new queue selection is made. The user then has a full
status for the new queue one cycle ahead of the WCLK rising edge that data
can be written into the new queue. That is, a new queue can be selected on
the write port via the WRADD bus, WADEN enable and a rising edge of WCLK.
On the 4th rising edge of WCLK, the FF flag output will show the full status of the
newly selected queue. On the forth rising edge of WCLK following the queue
selection, data can be written into the newly selected queue provided that data
and enable setup & hold times are met.
cycle after queue selection, which is one cycle before data can be written to that
queue. This prevents the user from writing data to a queue that is full, (assuming
that a queue switch has been made to a queue that is actually full).
based on a rising edge of WCLK. Internally the multi-queue device monitors and
keeps a record of the full status for all queues. It is possible that the status of a
FF flag maybe changing internally even though that flag is not the active queue
flag (selected on the write port). A queue selected on the read port may
experience a change of its internal full flag status based on read operations.
Operation and Figure 47, Full Flag Timing in Expansion Configuration for timing
information.
EXPANSION CONFIGURATION - FULL FLAG OPERATION
flags of all devices should be connected together, such that a system controller
monitoring and managing the multi-queue devices write port only looks at a
single FF flag (as opposed to a discrete FF flag for each device). This FF flag
is only pertinent to the queue being selected for write operations at that time.
Remember, that when in expansion configuration only one multi-queue device
can be written to at any moment in time, thus the FF flag provides status of the
active queue on the write port.
output have a High-Impedance capability, such that when a queue selection is
IDT72P51339/72P51349/72P51359/72P51369 1.8V, MQ FLOW-CONTROL DEVICES
(8 QUEUES) 36 BIT WIDE CONFIGURATION 589, 824, 1,179,648, 2,359,296, and 4,718,592
The IDT72P51339/72P51349/72P51359/72P51369 multi-queue flow-con-
The multi-queue flow-control device provides a single Full Flag output, FF.
When queue switches are being made on the write port, the FF flag output
Note, the FF flag will provide status of a newly selected queue three WCLK
The FF flag is synchronous to the WCLK and all transitions of the FF flag occur
See Figure 44, Write Queue Select, Write Operation and Full Flag
When multi-queue devices are connected in Expansion configuration the FF
This connection of flag outputs to create a single flag requires that the FF flag
42
made only a single device drives the FF flag bus and all other FF flag outputs
connected to the FF flag bus are placed into High-Impedance. The user does
not have to select this High-Impedance state, a given multi-queue flow-control
device will automatically place its FF flag output into High-Impedance when none
of its queues are selected for write operations.
flag output of that device will maintain control of the FF flag bus. Its FF flag will
simply update between queue switches to show the respective queue full status.
on the 1-3 bit ID code (1 if two multi-queue are configured with a maximum total
of 256 queues, 2 if four devices are used totalling a maximum of 256 queues,
and 3 if there are up to eight devices with a maximum total of 256 queues) found
in the 1-3 most significant bits of the write queue address bus, WRADD. If the
1-3 most significant bits of WRADD match the 1-3 bit ID code setup on the static
inputs, ID0, ID1 and ID2 then the FF flag output of the respective device will be
in a Low-Impedance state. If they do not match, then the FF flag output of the
respective device will be in a High-Impedance state. See Figure 47, Full Flag
Timing in Expansion Configuration for details of flag operation, including when
more than one device is connected in expansion.
EMPTY OR OUTPUT READY FLAG OPERATION (EF/OR)
Ready flag output, EF/OR. The OR provides an empty status or data Output
Ready status for the data word currently available on the output register of the
read port. The rising edge of an RCLK cycle that places new data onto the output
register of the read port, also updates the OR flag to show whether or not that
new data word is actually valid. Internally the multi-queue flow-control device
monitors and maintains a status of the empty condition of all queues within it,
however only the queue that is selected for read operations has its Output Ready
(empty) status output to the OR flag, giving a valid status for the word being read
at that time.
data word is read from a selected queue, the OR flag will go HIGH on the next
enabled read, that is, on the next rising edge of RCLK while REN is LOW.
to show status of the new queue in line with the data output from the new queue.
When a queue selection is made the first data from that queue will appear on
the Qout data outputs 4 RCLK cycles later, the OR will change state to indicate
validity of the data from the newly selected queue on this 3
The previous cycles will continue to output data from the previous queue and
the OR flag will indicate the status of those outputs. Again, the OR flag always
indicates status for the data currently present on the output register.
based on a rising edge of RCLK. Internally the multi-queue device monitors and
keeps a record of the Output Ready (empty) status for all queues. It is possible
that the status of an OR flag may be changing internally even though that
respective flag is not the active queue flag (selected on the read port). A queue
selected on the write port may experience a change of its internal OR flag status
based on write operations, that is, data may be written into that queue causing
it to become “not empty”.
Ready Flag Timing for details of the timing.
EXPANSION – EMPTY FLAG OPERATION
flags of all devices should be connected together, such that a system controller
monitoring and managing the multi-queue devices read port only looks at a
single EF flag (as opposed to a discrete EF flag for each device). This EF flag
When queues within a single device are selected for write operations, the FF
The multi-queue device places its FF flag output into High-Impedance based
The multi-queue flow-control device provides a single Empty or Output
The nature of the first word fall through operation means that when the last
When queue switches are being made on the read port, the OR flag will switch
The OR flag is synchronous to the RCLK and all transitions of the OR flag occur
See Figure 48, Read Queue Select, Read Operation and Figure 51, Output
When multi-queue devices are connected in Expansion configuration, the EF
COMMERCIAL AND INDUSTRIAL
TEMPERATURE RANGES
AUGUST 4, 2005
rd
RCLK cycle also.