FT232H datasheet(38/65 Pages) FTDI

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Document No.: FT_000288

FT232H SINGLE CHANNEL HI-SPEED USB TO MULTIPURPOSE UART/FIFO IC

Datasheet Version 1.81

Clearance No.: FTDI #199

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 FT_SetBitMode D2xx driver 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

Name

Minimum Typical

Maximu

Units

Description

FSDO/FSC TS hold time

FSDO/FSC TS setup time

FSDI hold time

FSDI Setup Time

FSC LK low

FSC LK high

FSC LK Period

Table 4.5 Fast Serial Interface Signal Timings

FT232H Datasheet(PDF) 38 Page - Future Technology Devices International Ltd.