LOW COST - Small Size	Simple to use - Low Power
On-board Real Time Clock	On-board serial EEPROM
Note: We have limited numbers of these boards available. The plan is to continue to support existing customers but not to sell these to new users. If interrested in a new general purpose PIC controller - try the SIM_1A1
GPC_4A4 Info - Connections - Prices - Downloads
Supplied with pin headers installed. Right angle (as shown above) as standard. Straight pins, usually out the back of the board are also available on request. Think of it as a single chip processor. Simply build your application around it. Ideal for industry, hobby and education. Connection details - Pricing - Availability Notes A FEW DETAILS INTRODUCTION The GPC_4A4 is a small general purpose processor module that will accept a range of 18 pin PIC microcontrollers. It's designed to be mounted (normally vertically) on another circuit board. This board provides power and interfacing to the real world. The GPC_4A4 was designed originally to control one of our power supplies. Since then it's been used in other applications. Supported PIC micros include the popular PIC16F628 and the PIC16F88. Devices like the 74HC595 can easily be connected to expand the available I/O capacity. PROGRAM DEVELOPMENT Microchip manufacture the PIC micros. From their web site you can download MPLAB. This is a complete development system which runs under Windows. Visit Microchip for more detailed information and manuals. You will also need a chip programmer. Your development system will produce the code that goes into the PIC micro. A programmer gets it there. There are a number of options: The cheapest is to find a design on the web, build it yourself and download some support software. The advantage is cost. There are a few disadvantages. You have to build it and get it working without damaging too many chips. You have another unknown. You will be creating programs for your GPC_4A4; if it doesn't work, do you blame the program or the programmer. This sort of problem can be a nightmare to solve. Purchase a working programmer. Microchip produce a device called Picstart Plus. This includes MPLAB, a programmer and plenty of documentation. The cost varies, but expect to pay up to $400 NZD (approx $200 USD. There are others available. PMB Electronics recommends the Warp-13 from Dontronics in Australia. There is a wealth of information available on the web. A search for PIC or Microchip will turn up plenty of leads. FEATURES The features avaliable depend to some extent on the chosen microcontroller. For example: The PIC16F84 is reprogrammable many times but does not include an Analog to Digital Converter (ADC). The PIC16F88 is reprorammable and includes the ADC. We use the PIC16C715 in a couple of applications because of low cost and it include an ADC, but is One Time Programmable (OTP). The GPC_4A4 includes two on-board low current relays. These provide a clean SPST output that can handle up to 1A @ 24V AC/DC. The other I/O lines are configured to be as general purpose as possible, while minimising the number of external components required for a typical application. This includes two I/O pins with 1K series resistors. These can be connected directly to LEDs. Another two, when used with a chip containing an ADC such as the PIC16C711, will accept applied voltages of up to 18V DC. These are ideal for monitoring 12V power supply and battery voltages, and also reading light levels and temperatures. FEATURE LIST Accepts many 18 pin PICs (16F84, 16F88, 16C715, etc) DIP CPU socketed for easy development. Crystal, Ceramic Resonator or RC clock (specify with order) ISP header on board. (optional, specify wth order) 10 to 14V DC power supply Serial EEPROM on board (24C64) Real Time Clock chip on board Accepts battery or super-cap for RTC backup 8 I/O lines connected to PIC 1 of the 8 I/O lines is the PIC external interrupt 2 relay outputs (optional, can be I/O lines) 15 pin SIP configuration 46mm x 28mm x 15mm deep (with relays) Mostly surface mount componentry  TO MAKE IT GO To make the GPC_4A4 operational you need a programmed PIC chip and a DC power supply. CAUTION Some of the I/O pins are connected dirrectly to the PIC chip. These must not be connected directly to the power supply pins.

CONNECTIONS The following table shows the function assigned to each of the 15 connector pins. If you are not familiar with the 18 pin PIC, the manual or data sheet will be required to sort out some of the meaning.

1	RLA	Relay A	.	normally open contact
2	RLA/RB1	Relay A	.	optionally RB1
3	RLB	Relay B	.	normally open contact
4	RLB/RB2	Relay B	.	optionally RB2
5	MCLR	10K +5V pull-up	digital input.	interrupt (ICSP)
6	AN1	voltage divider	analog or digital	analog input, accepts up to +18V
7	AN0	voltage divider	analog or digital	analog input. accepts up to +18V
8	RB4	1K	digital I/O	.
9	0V	0V common	analog input	0V
10	RB3	1K	digital I/O	.
11	+V	+Ve power supply	power	+10 to 14V DC
12	0V	0V common supply	power	0V
13	RB5	direct connect	digital I/O	.
14	RB6	direct connect	digital I/O	(ICSP)
15	RB7	direct connect	digital I/O	(ICSP)

assembled modules	package	part number	1 to 11	12 to 48	49 up
GPC_4A4, PIC micro project module	15 pin module	YTMGPC4A4-1	$30.00	.	.
GPC_4A4, as above but with digital I/O in place of relays.	15 pin module	YMGPC4A4-2	$28.00	.	.

Files available for Download
Circuit Diagram (pdf)	24C02, EEPROM Data (pdf)	.
24C04, EEPROM Data (pdf)	HT1381, RTC data (pdf)	.
Code example (.asm) (.hex) Application framework and RTC/EEPROM example	Code example #2 (.asm)	.
.	.	.

last updated: 10 January 2007