General Purpose Boards

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General purpose 28 pin PIC microcontroller board

Can be used as a stand alone controller for a variety of projects. For quick  projects it takes the hassle of having to bread board all the parts. Makes an excellent robot controller board. Includes, a 5v regulator, an RS232 transceiver, reset button, and two I2C eeproms. All pins (PortA, PortB and PortC) are conveniently brought out to headers. One can use male or female headers. The 3 pin OSC sip socket makes easy to change resonators. RS232 pins are Rx,Tx and Gnd and are wired to Portc Pins 6 and 7. This makes it possible to program the PIC while on the board using a bootloader. Designed to work with PIC16F87x and PIC18F2x2 mcus.


  • On-board regulator and power LED
  • On-board  RS232 driver chip
  • All PIC pins are brought to headers
  • CB28A has room for 2 I2C eeproms
  • Reset button
  • Selectable power, on-board/external
  • Small and economical

PortA Pins 5-0 + -

Vin 7-16vdc


PortC 0-7  PortB 0-7 + -

Two 256kbit I2C eeproms for storage

CB28PCB bare pcb

Note: Requires installing SMD (surface mount devices) parts.

The kit incorporates numerous surface mount parts (SMD). The user will have to install the remaining  SMD parts (resistors,caps and the SOIC eeprom).Assembly of this kit requires that the user has the necessary tools and skills to work with SMD (surface mount device) components. If one is not comfortable with  soldering miniature parts, then it is advisable to seek assistance from someone who is capable to do so. Small mistakes can cause many frustrating hours of grief in trouble shooting!Minimum tools required: A  fine point low power (25w max) soldering iron and thin solder. Ideally, 0.022" diameter (or less) silver-bearing non-corrosive rosin core should be used. In addition. narrow needle nose pliers, diagonal cutting  pliers, good quality tweezers, large magnifying glass, volt-ohm meter, and a 7 to 12 vdc power supply.Make sure that you work in a clean well lighted area and have adequate desk area. If you have carpeting then  please be aware of static discharge as well as accidentally losing tiny components in the carpets fiber. SMD capacitors and resistors are very tiny and can quickly become invisible in the carpeting.

A232P88 Controller Kit


The A232P88 is a compact controller board which includes a PIC16F88, a Max3232 IC, and voltage regulator. It can be powered externally or can draw its power from the PC’s serial lines, by using the voltage on the RTS and DTR lines via protection diodes and then passing it through a voltage regulator. The PIC can be programmed via a 5 pin header. All the PIC pins are available for use. The circuit is designed to use the PIC16F88’s internal oscillator. Please note that this kit requires soldering surface mount devices (see note above). Ideal for small sensor and switch projects.

A232P88 (shown assembled)


Example of the A232P88 connected to a sensor


In this example the A232P88 is connected to a SHT11 temp/humidity sensor from Sensirion Inc. Power is derived from the PC’s serial lines. The PIC16F88 was programmed via the board’s 5 pin header. On the right, is the serial I/O output as seen in a terminal.


All Rights Reserved, Copyright (c) COMPSys , 2018

Updated on:

February 16, 2018 

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