After such a good response to Mr. Baybus, I decided to up the ante. I wanted temperature sensing and light control, as well as a more refined interface. I also wanted a chance to write much, much better code as Mr. Baybus was most definitely a kludge. This led to the design of Mr. Baybus 2.
Mr. Baybus had a few problems I wanted to take care of. One being price, it cost way too much compared to its utililty value, which is normal for projects like this, but still…
Mr. Baybus 2 uses a much more sophisticated microcontroller, a PIC 16F870. This is a 28-pin SDIP style chip, lots more I/O pins, an onboard UART, and even an ADC. This little guy also has twice the instruction memory, so I had more freedom to make the interface somewhat more sleek, and add more features. The benefit of more pins is CHEAPER LCD. The previous serial LCD ran about $42 shipped, which is semi-high for a serial LCD in general, but it was a CrystalFontz so at least it was high quality. Anyways, now I can move to a simple HD44780 based parallel LCD (by CrystalFontz, of course). These run around $20 shipped, and even less from other places selling generics.
- Three On/Off Fan controls
- One 12V Light control (Neons, etc)
- Two centrigrade temperature sensors
- 20×2 screen (any HD44780 compatible will work)
- Simple, menu-driven style interface
- Stores fan status in non-volatile memory
A slight update to the original. I decided I wanted to re-write it in C as an exercise. While I was at it, I figured I’d add a feature or two.
Pretty basic, a complete re-write in C, Hi-Tech PICC to be exact. It’s a great compiler for the PICs and gave me opportunities to re-write the LCD, ADC and DELAY libraries in C.
- New program-loop idea, worked well
- Strobe mode for Light output
- Temperatures in Celcius or Fahrenheit
All files for Mr. Baybus 2 are available at GitHub.