DS_FT2232D Datasheet, PDF (49/61 Pages) List of Unclassifed Manufacturers – Future Technology Devices International Ltd

Document No.: FT_000173
FT2232D DUAL USB TO SERIAL UART/FIFO IC Datasheet
Version 2.05
Clearance No.: FTDI# 127
Figure 8.14 Fast Opto-Isolated Serial Signal Timing Diagram
Time
Description
Min
Max
t1
FSDO / FSCTS hold
5
-
ns
time
t2
FSDO / FSCTS
5
-
ns
setup time
t3
FSDI hold time
5
-
ns
t4
FSDI setup time
10
-
ns
t5
FSCLK low
10
-
ns
t6
FSCLK high
10
-
ns
Table 8.15 Fast Opto-Isolated Serial Signal Timing Diagram
Unit
Outgoing Fast Serial Data
To send fast serial data out of the chip, the external device must clock. If the chip has data ready to
send, it will drive FSDO low to indicate the start bit. It will not do this if it is currently receiving data from
the external device.
Figure 8.15 Fast Opto-Isolated Serial Data Format - Data output from the FT2232D
Notes:-
(i) Start Bit is always 0.
(ii) Data is sent LSB first.
(iii) The source bit (SRCE) indicates which channel the data has come from. A „0‟ means that it
has come from Channel A, a „1‟ means that it has come from Channel B.
(iv) If the target device is unable to accept the data when it detects the start bit, it should stop
the FSCLK until it can accept the data.
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