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Building STK500 AVR ISP programmer with USB

A programmer adapter is one of the first things to get when starting with microcontrollers. Luckily, it is not hard to build a working programmer almost for any microcontroller, as there are tons of open-source projects. I decided to make my own stk500 compatible programmer, which is taken from tuxgraphics.com. I did not look for the same parts as in the original schematics but used what is on the desk. As a result, I got a mix of through-hole and SMD PCB, which does the job. Short info about STK500 V2 programmer This STK500 V2 adapter is a clone of the original AVR STK500 programmer. It works on all leading platforms, including Windows, Linux, BSD, and macOS X. This is mainly because USB to serial converter  –  FT232RL chip has full driver support. The main reason to build it is that the programmer works in AVRstudio, where microcontrollers can be programmed fluently from the same IDE. Besides, it works fine with AVRDude – which would be the primary application for Linux users. This clone gained quite significant popularity so that you can find many variations – mostly different PCB versions. Therefore, mine is yet another PCB.

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Yet Another Simple AVR ISP cable

Probably this programmer cable can be found on every AVR fan website. It is straightforward and easy to build. You need a few passive components that can be packed inside the LPT connector. From my perspective, I wouldn’t recommend using this one ISP programmer if you are more serious about microcontroller projects because it has poor computer port protection. It connects directly to the LPT port without precautions. I recommend using a similar ISP circuit with buffer IC between LPT and target board. But let’s don’t pretend like we are brilliant. The whole beauty is in its simplicity. This thing does its job perfectly as long as the target board power supply is OK.

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AVRISP is a very popular Parallel port programmer for flashing AVR type microcontrollers. Earlier I used programmer connected to com port, but frequently I needed this port for other purposes; I decided to make it work on the parallel port. The programmer on a parallel port is much simpler than connected to a serial port because there is no needed voltage adapter like MAX232. You can only connect your MCU directly to the port. But for safety reasons, there is good practice to use buffer ships like 74HC244. The header for programmer I used standard 6 pin ISP header.

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