PyFtdi

Overview

PyFtdi aims at providing a user-space driver for modern FTDI devices, implemented in pure Python language.

Modern FTDI devices include:

  • UART-only bridges

    • FT232R (single port, clock up to 6 MHz, 3Mbps)

    • FT230X (single port, clock up to 48 Mhz, 3Mbps)

  • UART and multi-serial protocols (SPI, I2C, JTAG) bridges

    • FT2232D (dual port, clock up to 6 MHz)

    • FT232H (single port, clock up to 30 MHz)

    • FT2232H (dual port, clock up to 30 MHz)

    • FT4232H (quad port, clock up to 30 MHz)

Other FTDI devices could also be supported (including FT232* devices), although these devices are not a primary goal for PyFtdi, and therefore have not been tested with PyFtdi.

Primary goals

PyFtdi currently supports the following features:

  • UART/Serial USB converter, up to 6 Mbps (depending on the FTDI device capability)

  • Bitbang/GPIO legacy support, 8 pins per port

  • SPI master, with simultanous GPIO support, up to 12 pins per port

  • I2C master, with simultanous GPIO support, up to 14 pins per port

  • (JTAG master)

  • Prelimiary EEPROM support (R/O access + R/W for serial/product/manufacturer)

PyFtdi provides a pyserial compliant API, so it can be used as a drop-in module to access USB-serial converters based on FTDI devices.

Potential API break

Starting with version v0.40.0, several API changes are being introduced. While PyFtdi tries to maintain backward compatibility with previous versions, so of these changes may require existing clients to update calls to PyFtdi.

Do not upgrade to v0.40.0 or above without testing your client against the new PyFtdi releases. PyFtdi versions up to v0.39.9 keep a stable API with v0.22+ series.

Major changes

  • read methods now return bytearray instead of Array(‘B’) so that pyserial readline() may be used. It also brings some performance improvements.

  • PyFtdi URLs now supports bus:address alternative specifiers, which required to augment the open_*() methods with new, optional parameters.

  • SpiController reserves only one slave line (/CS) where it used to reserve 4 slave lines in previous releases. This frees more GPIOs when default value is used - it is nevertheless still possible to reserve up to 5 slave lines.

  • type hinting is used for most, if not all, public methods.

  • simplified baudrate divider calculation.