JOY-2-PIC Microchip PIC Programmer​

​Ever wish that your A8 could transform into a programming tool for those Microchip PIC MCU's that everyone's using for embedded projects now days?  Well even if this never crossed your mind, it did for a couple of guys on AtariAge, thus setting off on a journey that resulted in the JOY2PIC Programmer.

So how exactly does this work?  Through the use of a voltage tripler, one of the joystick's 4 I/O lines is translated into what a PIC chip needs to initiate In Circuit Serial Programming. The other 3 bits of I/O are then used to communicate with the PIC, and through the use of a custom A8 software program, re-flash the program memory space with your choice of firmware (more info on PIC ICSP).
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JOY2PIC-STIK ready for use on a 1200XL
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JOY2PIC-STIK_gerbers.zip
File Size: 11 kb
File Type: zip
Download File
JOY2PIC-STIK_schema.pdf
File Size: 27 kb
File Type: pdf
Download File
A full BOM is included with the schematic download file. Uses the same ICSP programming circuit as the original JOY2PIC, so any of the flashing ATR's that worked with it, will also work with the STIK.

NEW      JOY2PIC-STIK

Supports 8, 14, and 18 pin PIC12xxxx and PIC16Fxxxx series devices via the built-in Zero Insertion Force socket. No cables, chip adapters, or jumper selections required. So easy to use... Just pop in your PIC, plug it into your A8, load the flashing ATR, and press START to flash a chip
JOY2PIC_gerbers.zip
File Size: 9 kb
File Type: zip
Download File
JOY-2-PIC_schema.pdf
File Size: 19 kb
File Type: pdf
Download File
​Un-Assembled Printed Circuit Boards are available from OSH Park, and can be ordered by using the green order button (min order = 3 pcs).

However for larger quantities and/or faster shipping, you can use the provided gerber files to order from either ALLPCB or EasyEDA.

The Original JOY2PIC
Assembly Parts List

ICSP          Right angle break-away header
​JOY1          D-Sub 9F solder-cup connector
R1,R3        2.2K
R2              1K
C1-C5        0.1uf
C6              4.7NF (0.0047uf)
D1-D4       1N914 or 1N4148
Q1,Q2       PN2907A
Q3             PN2222A
​D5             Red LED

​PCB ordering, Schematics, PCB manufacturing files (gerbers) are all available for download to the left.

​For additional information, please reference the AtariAge Forum ICSP Programmer discussion thread.

And to access the open source project go to:  https://github.com/dmsc/atari-picprog

How to Create an Atari Executable from Microchip HEX

All firmware file downloads on this site are already in an Atari executable format.
--- NO FURTHER PROCESSING REQUIRED ---
The following program discussion applies to when you wish to convert a MicroChip HEX file into an Atari COM file.
PicProg Program Author's Notes
​Usage:

From the bwdos prompt, type:

READHEX SAMPLE.HEX SAMPLE.COM

Now, you see a prompt with the available PIC models. Select the one you want by entering the number and RETURN.

This takes a while, reading "SAMPLE.HEX",  and producing "SAMPLE.COM". If you omit the output name in the command line, the default is the same as input with ".COM" instead of any existing extension. If you omit both parameters, the program asks for the input HEX file name.

After the end, press RETURN to return to DOS.

Now, you have in the disk a new binary, run it to program the PIC.

D1: SAMPLE

Now, pressing START begins the programming. The background color flashes to indicate progress.

The programming is a little slow, because I have limited the speed to one WSYNC per clock transition, this is about 7.7kbaud, and the programming protocol takes 28 bits for each word plus 3 ms of "programming time", so 2kword of PIC memory should take about 15 seconds.

​- Daniel Serpell
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This project was a joint effort by Daniel Serpell (dmsc) and myself, that began in December of 2015. The main thrust being to provide an inexpensive and easy to use method for the DIY person to update the firmware in the TK-II boards that were under development. It has since been put to use for a few other projects, and likely will find itself useful for even more to come.

As for the software applications, these are all Daniel's doing, as well as much of the overall hardware design. I mainly added my PCB layout skills and also added a few more PICs to the device list that JOY2PIC can now program. Presently a fairly diverse selection of PIC chips can be programmed, able to cover various applications including USB, RS232, I2C, and SPI hardware interface support, while also delivering a multitude of I/O functionality.

The JOY2PIC is probably the first ever A8 -to- PIC programmer, and likely also the first to use the Joystick port. By leveraging the power within the Atari 8-Bit computer, it has been possible to keep the programmer hardware very simple and inexpensive. And due to this simplicity, it could even be easily constructed on a breadboard, although the PCB approach presented here would be a far more practical way to go.

- Michael St. Pierre