Com Pi

Sorry this product has been discountinued.

  • Hardware mounting kit and GPIO extension header included.
  • RS232 Master Port.
  • Control the Raspberry Pi over RS232 or connect to external serial accessories.
  • 1-Wire® to I2C host interface with ESD protection diode.
  • Stackable with other Raspberry Pi accessory boards.
  • Buffered 5V I2C port.
  • External 5V power input for 1-Wire® interface.

The Com Pi from AB Electronics is a communication add-on board for the Raspberry Pi supporting RS232 and 1-Wire® protocols. A 5V buffered I2C port is also provided on the board.

The Com Pi is pin compatible with the the Raspberry Pi model B+.

Introduction:

The RS232 port is connected to the UART port on the Raspberry Pi using a MAX3232 interface. The MAX3232 IC converts the 3.3V UART port to RS232 voltages allowing communication with RS232 compatible devices over a DB9 serial cable or with the use of a null-modem cable the board allows terminal access with linux on the Raspberry Pi using a terminal application. The RS232 port can be accessed through the DB9 port or the solder points on the PCB.

The 1-Wire® port is based around a DS2482-100 I2C to 1-Wire® bridge device. The DS2482-100 provides bi-directional protocol conversion between the I2C port on the Raspberry Pi and any attached 1-Wire® slave devices. An ESD Protection Diode is used to protect the Com Pi and Raspberry Pi from electrostatic spikes on the 1-Wire® port. Connections to the 1-Wire® port can be made through the RJ-12 socket or the solder points on the PCB.  Wiring diagrams for the RS232 and 1-Wire® ports can be found on the Com Pi datasheet.

A 5V input port is also provided allowing you to use an external power supply on the 1-Wire® interface, reducing the load on the Raspberry Pi. If you choose to use the external 5V input please remove the jumper on the board to isolate the Raspberry Pi 5V bus.

Datasheets

Com Pi Datasheet

DS2482S (1-Wire Interface)

MAX3232E (RS232 Interface)

Compatibility Chart

Model A Yes
Model B Yes
Model A+ Yes
Model B+ Yes
Model 2B Yes
Pi Zero Yes

Input Ratings & Specifications

Vdd (5V input pin): 5.0V

Maximum current on 1-Wire pins: ±20 mA

I2C SDA/SCL voltage: 5.0 V

I2C port current: 100 mA

Schematic

Click to download
Click to download schematic PDF.

Mechanical Drawings

Mechanical Drawing

Click image to enlarge

Sample Code & Tutorials

Configuring the RS232 communication on the Raspberry Pi

Configuring and using the 1-Wire® port on your Raspberry Pi


Product Code: ComPi

Important Information

This development board/kit is intended for use for ENGINEERING DEVELOPMENT, DEMONSTRATION, OR EVALUATION PURPOSES ONLY and is not considered by abelectronics.co.uk to be a finished end-product fit for general consumer use. As such, the goods being provided are not intended to be complete in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including product safety and environmental measures typically found in end products that incorporate such semiconductor components or circuit boards. Persons handling the product(s) must have electronics training and observe good engineering practice standards. This development board/kit does not fall within the scope of the European Union directives regarding electromagnetic compatibility, restricted substances (RoHS), recycling (WEEE), FCC, CE or UL, and therefore may not meet the technical requirements of these directives or other related directives.