Sergei Bezrukov writes:
It is not a rare phenomenon that some USB devices attached to a computer during power-up remain invisible to the OS after booting. This concerns home-made devices during experiments and also some commercial ones. To make them visible again one has to disconnect the USB plug and reconnect it again. This leads to excessive contact wear of the USB connector. It would be nice to have a way to reconnect the device without mechanically unplugging it. A trivial solution based on buttons/switches or relays won’t work because of their contact bouncing, which might confuse as device as well as the OS.
USB switch - [Link]
Brian Schmalz writes:
The UBW board is a small board that contains a Microchip PIC USB-capable microcontroller, headers to bring out all of the PICs signal lines (to a breadboard for example), only costs about $15-$20 to build and is powered from the USB connection. I designed this board to be a simple parallel port replacement tool for Bruce Shapiro for use in his bits-to-bytes-to-bots class. Apologies to all other ‘Whacker’ projects like EDTP’s Packet Whacker for stealing a great name <grin>. All tools used to design this project are free, and the design is open to anyone to use for whatever they wish. Please build your own and improve upon it! If you don’t want to build your own, you can buy them assembled and tested from SparkFun in two varieties – a built and tested small surface mount board, or a larger plated through hole kit for $5 less. SparkFun hosts a USB forum where the UBW is a common discussion topic. If you have a question, it may have already been answered there.
UBW – USB Bit Whacker - [Link]
FTDI Expands Vinculum-II Precompiled Firmware & Source Code Offering, enabling a substantial shortening of development time.
USB solutions specialist Future Technology Devices International Limited (FTDI) has introduced additional elements to its family of precompiled, bridging ROM files that support Vinculum-II (VNC2) USB host/device controller ICs. These files can be loaded directly into a VNC2 IC and utilised in order to perform basic data transfer operations between common interfaces. Interface options include SPI, UART, USB host and USB device, with data operations such as mass storage, human interface devices, and communication device class. This provides engineers with off-the-shelf software capabilities that can be immediately implemented – enabling shorter development time and resulting in faster time to market.
The new ROM files from FTDI are:
- SPI master to UART – the bridging of a VNC2 UART to the VNC2 SPI master for controlling SPI slave devices. Data is transferrable in both directions.
- SPI slave to USB memory bridge – the bridging of a USB memory (Flash drive) device present on the VNC2 USB host port to a SPI interface.
- A SPI master to USB human interface device (HID) – the bridging of a USB HID class device (such as a keyboard or a mouse) present on the VNC2 USB host port to a SPI interface.
- A UART to communication device class (CDC) modem – the bridging of a CDC device present on the VNC2 USB host port to a UART interface, with data transferrable in both directions.
- A UART to FT232 host – the bridging of a FT232/FTxxx class device present on the VNC2 USB host port to a UART interface.
- A UART to USB HID Class Host – the bridging of a HID class device present on the VNC2 USB host port to a UART interface.
- A UART to USB Memory – the bridging of a USB memory device present on the VNC2 USB host port to a UART interface.
Each of the precompiled ROM files is accompanied by the source code, to allow users to modify and expand upon the reference software. Complete documentation and application notes are also included, which provide engineers the context of the implementation.
The new ROM files can be downloaded free of charge at: http://www.ftdichip.com/Firmware/Precompiled.htm
Simplify a development of USB devices by off-the-shelf files from FTDI - [Link]
The serial UART is a common interface used by many chips and devices. Ginpb designed a USB-to-UART adapter that works with 3.3V and 5V UART signals. The device is based around the FTDI FT232BL USB-to-UART IC with an added 3.3V power supply. The different interface levels are selected by an on-board jumper.
Simple USB to UART adapter that works with 3.3V and 5V UART signals - [Link]
With this circuit you can log serial (UART) data to an USB thumb drive and record data over a long period without the need of a PC. Simply connect your system to the logger and plug in an USB keydrive. All incoming data is logged to a file on the memory stick.
- No smd components are needed.
- Firmware is open source.
- Single power supply voltage: 5V (about 80mA).
- Connection to your circuit with only three lines: +5V, GND, uC-Tx.
- UART baudrate can be adjusted with a configuration file on the USB keydrive.
USBStickLogger – Log serial data to an USB thumb drive - [Link]
Out of anger for a bad product from Conrad I developed this six channel relay card. It supports some nice features like USB and programmable timers. It can also be controlled manually or with a RC5 compatible remote control. Very handy when it comes to control light sources and computer peripherals from a terminal.
Six channel USB relay card - [Link]
This piece of hardware enables you to connect a number of TWI sensors to your PC via USB. At this moment the board supports one SHT11 and up to 8 DS1621. These sensors can measure temperature (DS1621) and relatvive humidity (SHT11). A PC client is capable of writing the data into a MySQL database. The data can then be visualized with Gnuplot using the plotting tool, providing a multitude of options.
USB sensor board - [Link]
This page describes hardware and software design for digital USB FM transmitter, called FmStick. This hardware does not contain analogue parts (except RF part). The main idea – is to create transmitter, that looks like usb flash stick. This idea is not new, You can see some of this designs in market, like Griffi RocketFM or Keene USB FM Transmitter, both avaliable on Amazon. But device, described below – is different. It does not have analogue sound parts at all, and it supports RDS, and it is powerful.
The main features of this device are:
- Transmit Frequency: 76 … 108 Mhz
- Transmit Power: -60 … 20 dBm
- Audio Compression: Yes
- Audio Limitation: Yes
- Audio Signal Measurements: Yes
- Pre-Emphasis: 0/50/75 uS
- RDS: Yes
- RDS RadioText: Yes
- RDS Time: Yes
- Drivers Installation Needed: No
- Software Needed: No
- LEDs That shows state: Yes
- External power needed: No
FmStick Digital USB FM Transmitter - [Link]
On my desktop PC I have a speakers and a headphones. Usually I use headphones, but when I need to switch to speakers I need to physically plug in speakers instead of headphones to my PC’s soundcard. I wanted to solve this problem for a long time, but never get around of that until recently I saw this posted on Hackaday.
And so I’ve decided to build my own really simple audio multiplexer.
USB Audio Multiplexer - [Link]
The FT232R is the latest device to be added to FTDI’s range of USB UART interface Integrated Circuit Devices. The FT232R is a USB to serial UART interface with optional clock generator output, and the new FTDIChip-ID™ security dongle feature. In addition, asynchronous and synchronous bit bang interface modes are available. USB to serial designs using the FT232R have been further simplified by fully integrating the external EEPROM, clock circuit and USB resistors onto the device.
The FT232R adds two new functions compared with its predecessors, effectively making it a “3-in-1” chip for some application areas. The internally generated clock (6MHz, 12MHz, 24MHz, and 48MHz) can be brought out of the device and used to drive a microcontroller or external logic. A unique number (the FTDIChip-ID™) is burnt into the device during manufacture and is readable over USB, thus forming the basis of a security dongle which can be used to protect customer application software from being copied.
The FT232R is available in Pb-free (RoHS compliant) compact 28-Lead SSOP and QFN-32 packages.
Single chip USB/UART FT232R - [Link]