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The FT232H is the single channel version, the FT2232H is the dual-channel, and there is also anFT4232H quad channel part.
While these are all logically the same, with different numbers of UART channels, there are some performance and functional differences between them.
The FT232H has merely 1 kB of ring buffer, which can be overwhelmed if running at a high baud rate, and with a slow offtake by the host device. The FT2232H has 4 kB ring buffer per channel, much better in avoiding buffer overruns.
Another difference, which may not be relevant to the task at hand, is that the FT2232H supports 16 GPIO pins via its internal 8051 emulation. There have been useful applications designed to leverage these GPIOs, but you may not need this.
FT232H - Hi-Speed Single Channel USB UART/FIFO IC
Operating at USB Hi-Speed 480Mbps rate, this fast single channel bridge chip features
either a flexible serial interface or parallel FIFO interface,
with data transfer speeds up to 40Mbytes/s.
Using a serial EEPROM interface, this device can be configured for a wide variety of asynchronous and synchronous serial standards,
such as JTAG, SPI, I2C and UART as well as synchronous and asynchronous parallel FIFO interfaces.
In addition, this device features the new synchronous, half-duplex FT1248 bus,
which allows an engineer to trade off bandwidth for pin count using 1, 2, 4, or 8 data lines at up to 30Mbytes/s.
The I/O structure is 3.3V with built-in tolerance for 5V, allowing the designer maximum flexibility when interfacing with FPGAs.
On-board voltage regulation provides 3.3V and 1.8V supplies from a 5V source, as well as a power-on-reset function.
FTDI provides royalty-free virtual com port and D2XX drivers for Microsoft Windows (XP – Windows7),
Apple Mac OSX, and Linux. This 48 pin device is available in either LQFP or QFN packaging, and is ROHS compliant.
The FT2232H is FTDI’s 5th generation of USB devices.
The FT2232H is a USB 2.0 Hi-Speed (480Mb/s) to UART/FIFO IC.
It has the capability of being configured in a variety of industry standard serial or parallel interfaces.
Building on the innovative features of the FT2232,
the FT2232H has two multi-protocol synchronous serial engines (MPSSEs)
which allow for communication using JTAG, I2C and SPI on two channels simultaneously.
The FT2232H is available in Pb-free (RoHS compliant) 64-pin LQFP and QFN packages.
The FT4232H is FTDI’s 5th generation of USB devices.
The FT4232H is a USB 2.0 Hi-Speed (480Mb/s) to UART IC.
It has the capability of being configured in a variety of industry standard serial or parallel interfaces.
The FT4232H features 4 UARTs. Two of these have an option to independently configure an MPSSE engine,
this allows the FT4232H to operate as two UART/Bit-Bang ports plus two MPSSE engines used
to emulate JTAG, SPI, I2C, Bit-bang or other synchronous serial modes.
The FT4232H is available in Pb-free (RoHS compliant) 64-pin LQFP and QFN packages.
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原文地址：http://www.cnblogs.com/shangdawei/p/4817748.html
