ft232hq Future Technology Devices International Ltd., ft232hq Datasheet - Page 40

• Manufacturer Part Number: ft232hq
• Description: Ft232h Single Channel Hi- Speed Usb To Multipurpose Uart/fifo Ic
• Manufacturer: Future Technology Devices International Ltd.

4.9 Fast Serial Interface Mode Description
Fast Serial Interface Mode provides a method of communicating with an external device over USB using 4
wires that can have opto-isolators in their path, thus providing galvanic isolation between systems. Fast
serial mode is enabled by setting the appropriate bits in the external EEPROM. The fast serial mode can
be held in reset by setting a bit value of 0x10 using the Set Bit Bang Mode command. While this bit is set
the device is held reset – data can be sent to the device, but it will not be sent out by the device until the
device is enabled again. This is done by sending a bit value of 0x00 using the Set Bit Mode command.
When the FT232H is configured in Fast Serial Interface mode the IO timing of the signals used are shown
in Figure 4.17 and the timings are shown in Table 4.5 Fast Serial Interface Signal Timings.
Figure 4.17 Fast Serial Interface Signal Waveforms
Table 4.5 Fast Serial Interface Signal Timings
Name
t1
t2
t3
t4
t5
t6
Min
20
20
20
1
1
5
Copyright © 2011 Future Technology Devices International Limited
Typ
FT232H SINGLE CHANNEL HI-SPEED USB TO MULTIPURPOSE UART/FIFO IC
Max
9
Units
ns
ns
ns
ns
ns
ns
FSDO/FSCTS output delay
FSDI setup time
FSDI hold time
FSCLK period
Comments
FSCLK high
FSCLK low
Document No.: FT_000288
Clearance No.: FTDI #199
Datasheet Version 1.0
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