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]
Open source application for charting data sent via RS-232 port in real time.
SerialChart – Analyse and chart serial data from RS-232 COM ports – [Link]
nneth Finnegan has been working on thermocouple adapter called SerialCouple – [via]
The SerialCouple line of boards are simple, easy to use single-channel thermocouple adapters, meant to be an interface between a thermocouple and a computer or other embedded system. Shown in the pictures are the model one boards, which are meant to be plugged into FTDI-like USB-to-Serial adapters, but a second model based on RS-232 is in the works.
SerialCouple thermocouple adapter v1 – [Link]
element14, Microchip and Matrix introduce the new PIC18 Flowcode Developers Kit. Lowers the barrier to electronics design with easy to use Graphical Programming
30 January 2012 – London, element14, the first collaborative global electronics community from Premier Farnell plc (LSE:pfl), has teamed up with Microchip and Matrix to introduce the new PIC18 Flowcode Developers Kit. This innovative development and demonstration kit is designed to offer a hands-on, easy approach to electronics design using Flowcode, one of the world’s most advanced graphical programming languages for microcontrollers.
The development platform is based on a Microchip PIC18F26J50 low power, 8-bit PIC18F26J50 microcontroller, and is integrated with temperature sensor, capacitor touch sensor and potentiometer to help developers verify programs designed using Flowcode.
“The new PIC18 Flowcode Developers Kit is an innovative, fully featured yet low cost solution designed to help developers realize their designs in working hardware,” says Mike Powell, Technology Development Manager, Premier Farnell. “Optimized for Flowcode development, the board has several expansion options, it can be used as a black box and is mounted with a PIC 18 device that is low power, but high performance.
The competitive advantage of Flowcode is that it allows those with little-to-no programming experience to create electronic systems in minutes. Flowcode supports code generation for the PIC® (PIC12, PIC16, and PIC18 series ), PIC24 and dsPIC® series of microcontrollers. The professional edition includes drivers for a range of sub-systems including LCDs, keypads, seven-segment displays, ADC and PWM, as well as communication protocols including I2C, SPI, RS-232RS-232, Zigbee and TCP/IP, among others.
Flowcode is compatible with Microchip’s PICkit programmer as well as third party programmers. It is also compatible with the HI-TECH C compiler. A ‘Lite’ version of Flowcode 4 is included in the kit.
For more information visit element14.
At purchase of any HAMEG digital storage oscilloscope from 7xx,10xx,15xx to 20xx series within this year, you wil gain the serial bus analysis option with a value of 190 EUR for free.
Together with a lot of useful functions which new HAMEG HMO digital storage oscilloscopes feature, HAMEG Instruments (a Rohde&Schwarz company) offers an extra bonus. At purchase of any of the above-mentioned oscilloscopes until the end of year 2011, you will gain the option 2011 for free – a license key enabling to analyse I2C, SPI a UART/RS-232 serial bus. Thanks to this function you can save a lot effort at development or service of devices, which use these communication protocols.
The option HO011 uses analog inputs and the trigger input, thus it isn´t necessary to buy any external logical sond. It offers a real time hardware accelerated decode. Values are displayed colour coded for intuitive analysis and an easy overview. Up to 4 lines are displayed for a comfortable display of decoded values. Decoding is into ASCII, bináry, hexadecimal or decimal format. HO011 also features a powerful trigger to isolate specific messages. You can download the HMO user manual, where you can find the detailed description of serial bus analysing on pages 37-41.
Analyse I2C, SPI and UART/RS-232 for free! – [Link]
The PDP-10/X is a reimplementation of the PDP-10, with 512KW of memory, a line-frequency clock, an interface to an RS-232 terminal, and an interface to an ATA-2 disk, that I designed and built just for fun.
The FPGA PCB is a general-purpose FPGA board that I designed some time ago (but I tweaked it a little for use in the PDP-10/X). It is little more than a carrier for a XILINX SPARTAN-3E FPGA (XC3S500E-4) in a PQFP-208 package, along with the bypass capacitors, and the LDOs that generate the 2.5V (VDDAUX) and 1.2V (VDDINT) supplies. All of the I/O pins are powered by 3.3V.
FPGA board: PDP-10/X is a reimplementation of the PDP-10 – [Link]
This morning I decided its about time I learn how to use the UART hardware in most PIC microcontrollers. I started off with a USB-RS-232 converter that I got for US$3 from DealExtreme. There are a few reasons why I used a converter, firstly being because my main PC no longer has an RS-232 port since its old tech, but also because I thought it’d be alot neater for my projects to have a USB connection and it means I can interface with TTL signal levels (0-5v) instead of the RS-232 standards -12v – +12v which would have added complications, but we’ll get back to that just now…
Learning Serial Communication – [Link]
Back in the old days the COM port or known as RS-232 (EIA-232 standard) is one of the essential communications protocol and hardware use in many computer system installation start from small UNIX machine to the mainframe. The RS-232 protocol is used by terminal such as wyse60 or DEC vt100 which connected through direct cable or modem to the UNIX host or legacy system. Actually you could still tracked this history in the /etc/termcap file on many modern Linux distribution; later on I will use this table in our project for some terminal command’s information.
Working with AVR microcontroller Communication Port Project – [Link]
This project shows how to use RS-232 communication for PIC16F84 microcontroller. It is fully software controlled RS232 transmission and reception for PIC16F84. It displays received ASCII characters sent from PC via RS232 and their corresponding decimal value on the LCD. Microcontroller sends feedback of received characters back to the terminal window.
PIC16F84 Test Routine For RS232 Communication – [Link]
This is an electronic digital caliper to computer (RS-232) interface. This will work with the inexpensive calipers, micrometers and height gauges that are typically made in China. The connector on the measuring instrument will have 4 pins, and the owner’s manual will typically describe the output as 24 bit 90 kHz synchronous. This does not work the name brand instruments – Fowler, Mitutoyo, Brown & Sharpe, etc.
The caliper sends a burst of data approximately three times each second. Each burst contains 48 bits of data as shown in timing.pdf. The first 24 bits are the position relative to the zero point set on the caliper. The second 24 bits are the position relative to an arbitrary zero that does not change. This is sort of an absolute position, but the zero point changes each time the caliper loses power. Each 24 bit value is in ones compliment form (1 sign bit, 23 data bits). This allows for a 0 and a -0. The unit of measure is 1/20480th of an inch. [image source: www.hobbytoolsupply.com]
Digital caliper to computer (RS-232) interface – [Link]