PDSP16540 Datasheet, PDF (4/11 Pages) Zarlink Semiconductor Inc – 32K BUCKET BUFFER

PDSP16540
NAME
TYPE
IP31:0
I/P
D31:0
O/P
RS
I/P
WS
I/P
WEN
I/P
DAV
O/P
RMF
O/P
MD0
I/P
MD2:1
MD4:3
I/P
MD5
I/P
RES
I/P
GND
I/P
VCC
I/P
2
SIGNAL DESCRIPTION
32 bit input bus. If MD5 is high, pins IP16:31 are redundant
32 bit output bus. This bus will be high impedance until the Data Available Flag is active. It
then remains low impedance until the required amount of data has been read. D15:0
become inputs during reset, and may be used to define the operating conditions.
The read strobe must be continuous, and the rising edge transfers data to the output pins.
Write strobe used to load data into the internal RAM. This strobe may be asynchronous to
the read strobe, and may be continuous or intermittent.
Write enable which when low allows the write strobe to load data.
Data Available Flag. This signal goes active low when the required amount of new data has
been written to the RAM. The complete block of data will then be read from the RAM in
sequence using the read strobe. The next system component must be ready to accept the
information, which will consist of both new and old data, in amounts defined by MD2:1. The
flag will go in-active for one read strobe period every time new data is written to the RAM,
and stays in-active when the complete block has been transferred.
Read Me Flag. This signal goes active high when a user defined amount of new data has
been written to the RAM. It can go active before DAV goes active, and thus allows the
system to prepare itself for data when it becomes available. It stays active until the complete
block has been read.
When MD0 is low the block length is 1024 words. When it is high the block length is defined
in groups of 32 words by the data on D4:0 during reset.
MD2:1 define the amount of new data within the block length as defined above. The options
are 1024 (00), 512 (01), 256 (10), or the number defined in groups of 32 words by D9:5
during reset (11). When the number of new words is less than the block length defined by
MD0, the first words read from the RAM will be data previously stored.
MD4:3 define the number of new words which are written before the Read Me Flag goes
active. The options are 1024, 512, 256 or the number defined in groups of 16 words by
D15:10 during reset.
When this pin is high the device will support the real transform mode of the PDSP16510.
Only IP15:0 input pins are then used and 2 blocks are acquired before the flags go active.
Both blocks are then read in parallel using the 32 output pins.
When this pin is low outputs D15:0 become inputs, which are used to define the operating
mode if the internal options have not been selected. The input can be power on reset.
Four ground pins. All must be connected
Four +5 volt pins.All must be connected