V2DIP2-64 FTDI, V2DIP2-64 Datasheet - Page 14

• Manufacturer Part Number: V2DIP2-64
• Description: Interface Modules & Development Tools USB Vinculum-II 64 Pin Mod 2 USB Ports
• Manufacturer: FTDI

Specifications of V2DIP2-64

• Interface Type: USB, Serial, UART, FIFO, SPI
• Data Bus Width: Serial, 8 bit
• Operating Supply Voltage: 5 V
• Product: Interface Modules
• For Use With/related Products: VNC2-64
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

3.6.2 Timing Diagram – Asynchronous FIFO Mode Read and Write Cycle
When in Asynchronous FIFO interface mode, the timing of a read and write operation on the FIFO
interface is shown in Figure 3.3
Table 3.7 Asynchronous FIFO Mode Read Cycle Timing
In asynchronous mode an external device can control data transfer driving FIFO_WR# and FIFO_RD#
inputs. In contrast to synchronous mode, in asynchronous mode the 245 FIFO module generates the
output enable EN# signal. EN# signal is effectively the read signal RD#.
Current byte is available to be read when FIFO_RD# goes low. When FIFO_RD# goes high, FIFO_RXF#
output will also go high. It will only become low again when there is another byte to read.
When FIFO_WR# goes low FIFO_TXE# flag will always go high. FIFO_TXE# goes low again only when
there is still space for data to be written in to the module.
Figure 3.3 – Asynchronous FIFO Mode Read and Write Cycle.
Time
t10
t11
t1
t2
t3
t4
t5
t6
t7
t8
t9
RD# inactive to RXF#
RXF# inactive after RD# cycle
RD# to Data
RD# active pulse width
RD# active after RXF#
WR# active to TXE# inactive
TXE# inactive after WR# cycle
DATA to TXE# active setup time
DATA hold time after WR# inactive
WR# active pulse width
WR# active after TXE#
Description
Copyright © 2010 Future Technology Devices International Limited
`
and
Table 3.7
V2DIP2-64 VNCL2-64Q Development Module Datasheet Version 1.0
Min
100
100
30
30
1
1
0
1
5
5
0
Max
14
14
14
-
-
-
-
-
-
-
-
Unit
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
Document Reference No.: FT_000166
Clearance No.: FTDI# 155
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