Circuit board with LCD module removed
| Projects: RF LCD Module 08/16/98 |
These days, many people are getting pagers before they can drive cars. There's something wrong with that... I figured, rather than pay lots of money for a paging service and for the pager itself, I'd just build one.
True, the range is 30' rather than nationwide, but it is alphanueric, and once I build a WWW interface, it will have a nationwide range, I guess.
The device consists of a standard 16x2 character LCD module with a 14-pin interface, a PIC 16F84 microcontroller, a Holtek encoding/decoding pair, and an RF TX/RX pair. That's it.
The PIC interfaces directly to the LCD: it could simply display a message at powerup, but instead I input data through the Holtek chip and the RF link. The transmitter is hooked up to the computer, and can send any alphanumeric character to the LCD module.
The data rate is rather slow, which is a limitation of the cheap RF boards I use. You can either have money in your pocket or a fast pager, not both.
Circuit board with LCD module removed
RFLCD board with LCD module installed
| | |