Document No.: FT_000053
FT232R USB UART IC Datasheet Version 2.07
Clearance No.: FTDI# 38
7.5 LED Interface
Any of the CBUS I/O pins can be configured to drive an LED. The FT232R has 3 configuration options for
driving LEDs from the CBUS. These are TXLED#, RXLED#, and TX&RXLED#. Refer to Section 3.5 for
configuration options.
VCCIO
TX
RX
270R
270R
FT232R
TXLED#
RXLED#
CBUS[0...4]
CBUS[0...4]
Figure 7.5 Dual LED Configuration
An example of using the FT232R to drive LEDs is shown in Figure 7.5. In this application one of the CBUS
pins is used to indicate transmission of data (TXLED#) and another is used to indicate receiving data
(RXLED#). When data is being transmitted or received the respective pins will drive from tri-state to low
in order to provide indication on the LEDs of data transfer. A digital one-shot is used so that even a small
percentage of data transfer is visible to the end user.
VCCIO
LED
270R
FT232R
TX&RXLED#
CBUS[0...4]
Figure 7.6 Single LED Configuration
Another example of using the FT232R to drive LEDs is shown in Figure 7.6. In this example one of the
CBUS pins is used to indicate when data is being transmitted or received by the device (TX&RXLED). In
this configuration the FT232R will drive only a single LED.
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