DS_FT311D Datasheet, PDF (13/40 Pages) Future Technology Devices International Ltd. – The FT311D is a Full Speed USB host specifically targeted at providing access to peripheral hardware from an Android platform with a USB device port.

DS_FT311D USB ANDROID HOST IC Datasheet
Version 1.0
Document No.: FT_000660 Clearance No.: FTDI# 305
5.2.1 UART Mode Signal Descriptions
The UART signals are fixed on the I/O pins. Table 5.1 UART Interface, details the pins for each of the
UART signals.
Pin No
23
Name
Type
Description
uart_txd
Output _{Transmit asynchronous data output}
24
uart_rxd
Input
Receive asynchronous data input
25
uart_rts#
Output
Request to send control output
26
uart_cts#
Input
Clear to send control input
29
uart_tx_active output
Table 5.1 UART Interface
Transmit enable (typically used for
RS485 designs)
5.3 Pulse Width Modulation
FT311D provides 4 Pulse Width Modulation (PWM) outputs. These can be used to generate PWM signals
which can be used to control motors, DC/DC converters, AC/DC supplies, etc. Further information is
available in an Application Note AN_140 - Vinculum-II PWM Example.
The features of the PWM module are as follows:
- 4 PWM outputs
- Variable frequency
- Variable duty cycle
5.4 I2C
I²C (Inter Integrated Circuit) is a multi-master serial bus invented by Philips. I²C uses two bi-directional
open-drain wires called serial data (SDA) and serial clock (SCL). Common I²C bus speeds are the 100
kbit/s standard mode (SM), 400 kbit/s fast mode (FM), 1 Mbit/s Fast mode plus (FM+), and 3.4 Mbit/s
High Speed mode (HS)
An I²C bus node can operate either as a master or a slave:
 Master node – issues the clock and addresses slaves
 Slave node – receives the clock line and address.
FT311D provides an I2C master interface for connection to other I2C Slave interfaces up to 125kbit/s.
The master is initially in master transmit mode by sending a start bit followed by the 7-bit address of the
slave it wishes to communicate with, which is finally followed by a single bit representing whether to
write(0) to, or read(1) from the slave.
Copyright © 2012 Future Technology Devices International Limited
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