This USB to serial converter project is easy to build, it is simple and inexpensive. It is based on the FT230XS from FTDI Chip.
USB to Serial converter using FTDI FT230X - [Link]
CDC-232 creates a virtual COM port on PC that doesn’t have real RS- 232C port. It enables RS-232C communication (without control lines), after connecting the device and installing the driver.
Write the program to AVR, build the circuit, and connect the device to PC’s USB port. Install the driver on Windows. Access the device through generated virtual COM port from terminal software or your application. Control lines (DTR, DTS, RTS, CTS) are not used by the host application. Set the terminal software as “no flow-control”.
Windows requests the driver installation again when connected to other USB port. Detect the previously installed driver automatically. Another COM number will be assigned. If you set serial number in AVR (rebuild with modified usbconfig.h), you can get the same COM port at any USB port. However, you cannot connect multiple CDC devices of the same serial number.
Before detaching the device, close the COM port in terminal software or in your application. Otherwise, you cannot connect to the device again because of the broken file handle. Restart the terminal software or your application then. Switch to the fast transfer mode using “lowcdc.vbs” to get the baudrate higher than 9600bps.
CDC-232 – Virtual COM on ATMEL AVR - [Link]
VoCore is an open hardware runs OpenWrt. It has WIFI, USB, UART, 20+ GPIOs but size is only one inch. It helps you make a smart house or study embedded system.
VoCore is a coin-sized Linux computer with wifi. It is also able to work as a full functional router. It runs OpenWrt on top of Linux. It contains 32MB SDRAM, 8MB SPI Flash and using RT5350(360MHz MIPS) as its heart. It provides many interfaces such as 10/100M Ethernet, USB, UART, I2C, I2S, PCM, JTAG and over 20 GPIOs but its size is less than one square inch(25mm x 25mm).
VoCore: A coin-sized Linux computer with wifi - [Link]
Digispark Pro - The tiny Arduino IDE ready, usb and mobile dev board and ecosystem – cheap enough to leave in any project! Wi-fi, BLE, and 25+ shields!
Serial over USB debugging, USB programmable, 14 i/o, SPI, I2C, UART, USB Device Emulation, Mobile Development Ready, Optional BT, BLE, Mesh, and Wi-Fi.
The super small, dirt cheap, always open source, Arduino compatible, USB (and Mobile and Wireless!) development (and production) platform, and follow-up to the original Digispark.
Easier to use, more pins, more program space, more features, more reliable – supporting the entire existing Digispark ecosystem of 25+ shields and adding Wi-Fi, Bluetooth, BLE shields and more! Ready for all your projects – including mobile hardware development! All still super affordable!
The Digispark Pro Ecosystem is the cheapest, Arduino compatible development platform for Mobile and Wireless hardware development.
Digispark Pro – tiny, Arduino ready, mobile & usb dev board! - [Link]
With the rapid development of GPS (Global Positioning System) techniques, GPS gets wider application in many fields. GPS has features such as high precision, global coverage, convenience, high quality, and low cost. Recently, the use of GPS extends speedily from military to civilian applications such as automobile navigation systems which combine the GPS system, e-map, and wireless network. GPS is getting popular, and the market for GPS techniques is extending continuously.
UARTs provide serial asynchronous receive data synchronization, parallel-to-serial and serial-to-parallel data conversion for both the transmitter and receiver sections. These functions are necessary for converting the serial data stream into parallel data that is required with digital systems. Synchronization for the serial data stream is accomplished by adding start and stop bits to the transmit data to form a data character. Data integrity is ensured by attaching a parity bit to the data character. The parity bit is checked by the receiver for any transmission bit errors.
The circuit describes how to combine GPS into a navigation system by using a Philips 2-channel UART, the SC16C2552B. The SC16C2552B is a two channel Universal Asynchronous Receiver and Transmitter (UART) used for serial data communications. Its principal function is to convert parallel data into serial data, and vice versa. The UART can handle serial data rates up to 5 Mbit/s.
- SC16C2552BIA44 Dual UART, 5 Mbps (max.), with 16-byte FIFOs
- 80C51 CMOS 0 to 42 MHz Single-Chip 8 Bit Microcontroller
- 12 MHz Oscillator Clock
- 1.8432 MHz Oscillator Clock
- 22pF Capacitor – 2 Units
- 33pF Capacitor – 2 Units
- 0.1µF Capacitor – 2 Units
- 10 µF Capacitor – 2 Units
- 74LV04 Hex Inverter – 2 Units
UART in GPS navigation system – [Link]
Ralph shared his auto-reset feature of his Arduino board. He writes:
Various versions of the Arduino will reset the board by toggling the serial DTR line, a feature called auto-reset. Since it relies on the DTR line, it won’t work with TTL serial adapters that don’t break out the DTR line. After writing my half-duplex serial UART, I thought of using the TTL serial break signal which holds the line at 0V for several ms. Normal serial communications would also send 0V, but at 57.6kbps, it would never last more than 160us before returning to the idle high voltage state. So what I needed was a circuit would not reset when the line is low for 160us, but would reset when the line is low for 100ms or more.
Zero-wire serial auto-reset for Arduino - [Link]
Exar have announced the 5 mm square SP335 transceiver chip which supports RS-232, RS-485 and RS-422 serial standards. It is a single chip solution between the serial comms port and the UART or MCU allowing system designers to cater for multiple serial protocols over the same connector. The transceiver’s programmable end-of-line termination and multiple configuration modes allow all three protocols to be used interchangeably over the same cabling and connector without the need for additional switching components.
Built in protection tolerates direct shorts to DC or AC voltages as high as ±18 V and severe ESD events. The chip features a separate supply voltage for the logic interface pins, which can be as low as 1.65 V. This allows direct interface with low voltage UARTs and MCUs without the need for level shifters. It also supports data rates up to 20 Mb/s in RS-485/422 modes and 1 Mb/s in RS-232 mode and can be slew limited to 250 kb/s toggling a single control pin. With no inductors or magnetic components, the on-board charge pump generates the RS-232 bipolar voltage levels from a single supply (3.0 to 5.5 V) using just four external capacitors. [via]
Transceiver Chip Handles RS-232, RS-485 and RS-422 - [Link]
Pratham: Breadboardable PIC32 Breakout/Development Board With USB OTG , USB/SDCard/UART Bootloader. Gaurav Chaudhary writes:
Doing random projects with Microcontroller i always come into position when i need to have a bit more power and Peripherals then regular 8-bit micro or Arduino has to offer, but most of the powerful micro usually come in non-DIY Friendly SMD package or else they have very less pins like DIP-28.
Do what i was need is a fairly small breakout board kind of things which should be easy to handle and should contain few necessary peripherals like bunch of LED ,few switches , USB , EEPROM , VReference for ADC ,Oscillator and Voltage regulators too. and the board also need to be low cost so that i can leave in that in the application as it is. and most important things is the board should be breadboard compatible.
so here is the solution with all of the features i can think off.
Pratham: Breadboardable PIC32 Breakout/Development Board - [Link]
Embedded Lab’s new development board for PIC12F series microcontrollers:
The 12F series of PIC microcontrollers are handy little 8-pin devices designed for small embedded applications that do not require too many I/O resources, and where small size is advantageous. These applications include a wide range of everyday products such as hair dryers, electric toothbrushes, rice cookers, vacuum cleaners, coffee makers, and blenders. Despite their small size, the PIC12F series microcontrollers offer many advanced features including wide operating voltage, internal programmable oscillator, 4 channels of 10-bit ADC, on-board EEPROM memory, on-chip voltage reference, multiple communication peripherals (UART, SPI, and I2C), PWM, and more. Today we are introducing a new development board (rapidPIC-08 V1.0) for easy and rapid prototyping of standalone applications using PIC12F microcontrollers.
Rapid development board for PIC12F series microcontrollers - [Link]
Keyboard, display, sensor or other device can be connected by means of Bluetooth modules even without cables.
Many times, it´s more practical to have devices interconnected wirelessly. Whether we need a simpler transfer of values from some sensor or a more complicated data communication between two devices, Bluetooth modules will manage it without a long development. Bluetooth technology with their range of 10m or up to 100m (Class 1) usually suit to many purposes where a cable connection is undesired or even impossible.
Bluetooth modules from company Rayson are based on various Bluetooth chips from a renowned company CSR, which determine main features of a given module. On stock we keep several types for example the favorite BTM-112 (Class 2) or BTM-222 (Class 1). Modules contain their own firmware, so it´s not necessary to know a functionality of given Bluetooth chips in detail, but for the most of applications it is sufficient to use configuration commands sent via UART port.
Versatility of modules is mainly in the fact, that they are able to transfer virtually any data, that´s why they can be used for controlling of peripherals, audio transmission etc. and everywhere, where there range and data transfer speed of Bluetooth protocols are sufficient.
Where a cable can’t, a Bluetooth can - [Link]