UEXT

UEXT, which stands for universal expansion connector, is a connector layout supporting three common serial communication protocols. The standard UEXT connector consists of ten pins (two rows of five, with 0.1" spacing) and supports I2C, SPI, and RS-232 serial communication, as well as carrying +3.3V power and common ground. UEXT ports can be found on many devices made by Olimex Ltd. a Bulgarian Printed circuit board manufacturer known for their evaluation and development boards for microcontrollers and other electronic components.

Some devices use non-standard UEXT connector layouts. In particular the RS-232 protocol may not be implemented, since it generally requires extra logic level shifting hardware. In these cases the spare pins are usually assigned other purposes, such as connecting to a device reset line, so care should be taken to check the exact connector layout on the schematic of a particular device.

References

* [http://www.olimex.com/ Olimex.com] , Bulgarian PCB manufacturer, creator of the UEXT connector standard.
*Olimex [http://www.olimex.com/dev/pdf/LPC_E22xx_pdf.pdf LPC E2214 Development board Datasheet] , with standard UEXT pinout schematic on Page 4.