Clock interrupt The STC89C52 has three timer/counters (most of the 8051 chips have the first two, and the third one is pretty common). One of the modes for timer 1 is to count clock pulses in an 8-bit register and when FF is reached, reload the count register from a separate 8-bit register. Each time […]
Monthly archives: December 2015
POV source code – part 1
These posts relate to the previous few concerning the Banggood kit: Cross LED Dot Matrix Display Circuit Board Rotating Electronic Kit It uses an STC89C52RC microcontroller which is a (fairly) modern Chinese version in the 8051 family. You can program it in assembler, but I chose to use the C language for this project. The […]
Cheap POV (persistence of vision) clock kit
These kits are available on Banggood.com for about $11 shipping included. Tricky soldering, and they don’t come with any instructions. There are instructions available on the website – but not unless you read Chinese. The pictures on the website help though. Anyway, I recommend the kit. Even if you can’t get it working properly, it’s […]
ISP programmer for the STC89C51 and STC89C52
I couldn’t find an ISP (programmer) for the STC89C52RC that worked with modern versions of Windows. I found several programmers that work with other chips in the STC range. I did find one that worked on Windows XP, and with some hacking got it to work with Windows 7; however I had no luck with […]
Fast, small, and simple Arduino SPI RAM chip routines.
The 8-pin chip, 23LC1024, is a good candidate for adding extra RAM to simple Arduinos such as the Uno, Nano, Mini. It provides 128K of RAM (the ATmega328 chip that these Arduinos use only has 2K of internal RAM). The chip works at 5V (anything from 2.5V to 5.5V) and uses SPI so it only […]