Temperature Controller

[Mr Eastwood]

This is something I've been working on for the last 2 years in my spare time.  It's a ramp/hold temperature controller,  it controls temperatures up to 1300'c based on temperature profiles which are created in XML then sent to the controller via rs232, the unit has a internal logging facility to store each successful run operation; then you can pull the logs from memory to the PC to be displayed as a graph. It has a COM mode that allows you to send commands from the PC to it. This pic doesn't show the rs232 module board.

It's taken a long time to create as it's my first real project and everything I've learned I've had to pick up on the way.  I've really got hooked on electronics now and I'm keen to get this finished so I can get started on the next version.

[MJLorton]

Brilliant, hats off to you and thanks for posting.

Cheers,
Martin.

[Mr Eastwood]

Just a small update; after doing the top board I wanted something to fit into a project box, so I created a smaller 2 board version.





Here's a small time-lapse clip build showing the part construction of the main board.
http://youtu.be/NKsXdEf8vio

Since that version - I decided to try and do a PCB layout; which is done and almost ready to be sent off to be made into PCBs.

[blankfield]

Really nice project, are you using bluetooth for rs232 communication? And what is the purpose of the xml format? Xml is a little to redundant format of data like for MCU's.

[Mr Eastwood]

Really nice project, are you using bluetooth for rs232 communication? And what is the purpose of the xml format? Xml is a little to redundant format of data like for MCU's.

Hi blankfield,    yes the Bluetooth module is for rs232;  all setup etc is done remotely via a custom console application written in c#.  The XML is only used to create the firing programmes on the PC;  it's then parsed and compiled into nice compact binary format that then gets sent to the controller:  but you're completely right - you wouldn't use XML natively on such a small MCU.    The push buttons I used were a bit crappy, but they should work ok for a while at least!

[Mr Eastwood]

Just another update;  my PCB's arrived this lunch from China;  so I quickly hand placed a few parts to check the foot-prints; it looks ok, so I'll proably get one soldered-up tonight after work - can't wait!!

[MJLorton]

Great to see your progress...do keep us posted!

[Mr Eastwood]

I've now soldered up all the parts;  so all that is required is a stand-off connector for the Bluetooth module which I need to order and the board is complete!  Tonight I plan to power it up and get all the pots setup, and also check everything is working as it should.

Things left to do is to completely re-write the temperature profile editing PC software and to create a comprehensive operators manual and service document.

[Mr Eastwood]

Unbelievable!  it took 6 under-board wires and 2 track cuts and a 1 line change on the firmware to get it fully working;   well, at least I can move on now.

[SeanB]

So now on version 0.2 then. Glad you got it running without having to redo the board totally.

[Mr Eastwood]

Yup, 0.2 ;-)     when I did the boards I was so focused on messing up the footprints and drill sizes that I should have paid more attention to the layout.

[SeanB]

I see you also got the cable to the LCD slightly wrong, so the cable is incorrectly retained. That is a very easy mistake to make.

[Mr Eastwood]

I see you also got the cable to the LCD slightly wrong, so the cable is incorrectly retained.

thanks for spotting that,  I hadn't realized that until you said.

[SeanB]

Been there, did that, had to carefully undo the latches and undo the none openable tabs and then redo the cable as I only had the one connector.....

[MJLorton]

Thanks for showing us the progress AND the mistakes too...we all learn from that.

Hats off to sharp eyes Sean too!