LEAP#395 8051 Programming with SDCC
The main purpose of this program is simply to have something for testing the LEAP#394 AT89C2051 Programmer, and also my first trial of SDCC - Small Device C Compiler.
It is almost but not quite the simplest LED blinky program possible. It blinks an LED on P1_0, using a do-nothing loop to approximate 1Hz cycle time.
I’m impressed. For a chipset that is meant to be long dead, getting a C toolchain up and running on MacOSX and programming AT89C2051 devices was utterly painless.
As always, all notes, schematics and code are in the Little Electronics & Arduino Projects repo on GitHub
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LEAP#394 Arduino 8051 Programmer
I’ve been meaning to dive a bit deeper into Intel MCS-51/8051 devices and programming ever since I built a Electronic Clock Kit powered by an AT89C2051.
Reading the AT89C2051 datasheet, its seems programming is actually a quite straight-forward process - the only complication being the need for a 12V programming voltage in addition to standard logic high of ~5V.
So while I could go out and buy a programmer, I found the idea of building my own is very attractive for two reasons:
- it is a bit of a short cut to building familiarity with the chip and datasheet
- I can make sure it supports my host platform of choice - MacOSX
I borrowed some ides from similar projects, the result being a programmer on an Arduino Uno shield, with discrete charge pump for the 0V-5V-12V required for the various programming modes, and compatible with the Python-based, open source at89overlord programming software written by piotrb5e3.
As always, all notes, schematics and code are in the Little Electronics & Arduino Projects repo on GitHub
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LEAP#393 Dickson Charge Pump
The Dickson Charge Pump is a neat trick for multiplying an input voltage. It is basically a capacitor bucket-brigade, with diodes for flow control, and a switching signal to make it go. It is not the most efficient voltage booster, and cannot drive very high currents, but may be a convenient solution depending on the application.
The version I’ve implemented here runs on an Arduino with a 62kHz PWM signal and generates a zener-regulated 12V output from the 5V supply on the Arduino.
As always, all notes, schematics and code are in the Little Electronics & Arduino Projects repo on GitHub
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LEAP#392 BoldportClub Whiteboard
The BoldportClub project #22 whiteboard is a neat little “breadboard enhancer”, featuring variable and coin-cell power supplies and prototyping areas. As always, all notes, schematics and code are in the Little Electronics & Arduino Projects repo on GitHub
Here’s a simple demonstration using the 4 LEDs on the shroud as outputs for a 4-stage CD4060 ripple counter:
Also included is a sheet of StickerCAD icons. I used them on my laptop case - including a rebus if you look carefully;-)
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