PIC Microcontroller circuit board

Following on from the PC based LANc controller I needed to design a circuit board that would replace my laptop and fit into the underwater housing.

The solution is to use a PIC microcontroller. These chips are like a miniature PC. They have a processor, memeory and ports. The problem is how to write a program for them and then copy it into the PIC.

You can either write the program in ASSEMBLER language (uphill and not user friendly), and use a freebie asssembler program downloaded off the web, or blow some money and get some software that allows you to write in BASIC. I opted for the easy way as life is too short and bought Crownhill's - Proton Development Suite.

You then need a circuit board to write to the chip. There is a variety of USB and COM port versions. The COM port ones are cheap, under £10, but they only work on COM ports that provide +- 9 volts. Most laptops don't! Also make sure the programmer and software is compatible with your microcontroller.

I bought a JDM2 off of Ebay. You can download PicPgm to use with it. It works really well.

JDM2 serial pic programmer

 

The PIC microcontroller circuit board

The criterior I used to build this board was based on my experience with the PC based prototype and the number of camera functions I can control. Tony Birchley was willing to fit 8 sliding magnets to the housing which in turn would pull in the reed switches mounted on the boards, inside the housing. No holes!

Specification - You can read my specification here

I chose to use the PIC16F628A controller. It has two 8 pin ports. The circuit design looks like this:

Nigel Ealand LANc circuit

 

The main and second switch boards look like this:

Main LANc control board Second board with reed switches

 

Viewfinder using an external monitor

The advantage of the Sony HC9 is that it has an AV socket. If you do a Google search for 3.5" TFT monitor you should find some cheap monitors like this one I got from Maplins:

3.5 inch TFT monitorright angle sony AV cable from Action Cameras

I also bought a right angle AV cable from Action Cameras. This saves a nasty cable bend in the housing and keeps the cable short. I'm not sure if they still make them. The alternative I've found is at Extreme Recall in the USA.

Battery pack

These monitors operate on 8-12 volts. The circuit board has a 5v reed relay fitted to switch the monitor power. I used some AA holders to create a 12 volt supply and power both the LANc circuit board and the monitor.

If you don't require a monitor the LANc board can be wired to the LANc socket jack to pick up the power from the camera.

AA battery holders

....and here is the kit all together.

DONATION

You are more than welcome to download and use this information. If you need help then send me an email.

If you would like to give a donation I would certainly appreciate it. All monies go to keep our diving club viable so that I can continue doing a sport I love so much.

 

DOWNLOADS

Circuit drawing PDF

Circuit board layout PDF

LANc Specification

LANc PCB bitmap