Sorry its taken so long to post an update. I’m very busy at the moment with my PhD and I’m about to move house again.
Although I do have a couple of updates to post, I simply don’t have the time to write any detailed posts, but heres an outline of things to come:
I’ve decided to scrap the current word clock circuit. The I²C communications to the real time clock (RTC) only seem to work provided I don’t add any other functions to the microcontroller and I have a feeling that when it comes to getting the master/slave protocol to work with the other microcontroller, I’ll have even more trouble. I’ve decided to redesign the circuit, based around 64 pin surface mount PIC with a built in RTC. This will vastly simplify the design, although it does mean learning surface mount soldering.
In addition, I’ve got all the parts for my CNC z-axis (stepper motors, linear bearings etc), I just have to build it. I’ve also designed and built the stepper motor driver. I just need to find time to test this and blog about it. I’ll try and post a video of the motors moving when its done.
I’ve not forgotten about this blog, or my projects, I just need a few spare days to catch up on my to do list.
Ok, I’ve finally found time to make a new post about my Sunrise Word Clock. My previous attempt at making the circuit work on breadboard didn’t go so well. I assume this is because of the poor connections that the breadboard provides and could also have been because of poor layout choices. Anyway, I’ve rebuilt my prototype on strip board and i’m going to try and explain the circuit here.
The microcontrollers that i have readily available are PIC16F887. These come in a 40 pin DIP package
The interfaces i require are:
- 2 I2C pins
- 2 Vdd pins
- 2 Vss pins
- 3 programming pins
- 1 pin for analogue to digital
- 4 pins for button inputs
- 6 pins for LCD interface
- 22 pins for the Front LEDs
- 1 PWM Power LED Channel
- 2 Crystal Pins
Total pins required = 45… oh dear
My next project is a word clock inspired by drj113’s instructible on making a word clock.
My design differs from drj113’s original considerably
- Rearranged lettering on the front, giving am and pm yet maintaining a compact design
- Dimmable LED channels so that i can create smooth time transitions
- Light sensor so that brightness can be adjusted according to ambient light
- Superbright power LEDs on the back so that the clock can be used for dawn simulation.
I’ve also decided the frame of the clock will be aluminium, touching this aluminium should toggle the power LEDs on and off (with smooth transition).