Exploring STC MCU part 6 – Feeling the environment

STC microcontrollers sometimes comes with built-in ADC. It can be a little bit tricky to use as the relevant pins have to be switched between analog and digital mode.

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Exploring STC MCU part 5 – Speak up

It is finally the time to get the chip to speak up – start communicating over the serial link. Keeping true to the nature of my previous example code, the serial driver code will adapt to the oscillator frequency and baudrate you wish to use.

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Exploring STC MCU part 4 – Better times

Remember back in part 3 I wrote the timing code? That code only works with a 24MHz clock. And I didn’t have the watchdog running yet. So I am gonna fix it.

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Exploring STC MCU part 3.5 – bug explained

The bug I encountered on STC15W4K61S4 is resolved: this chip, being much more complicated than the traditional 8051 my textbooks was written for, have a bit of quirks that can break code compatibility between them.

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Exploring STC MCU Part 3 – Samples, bugs, and the first lines of code

I am digging deeper into the STC 8051 ecosystem by attempting to write my first bits of actual code on this platform. This experiment took me a few days to execute as I need to wrestle a few bugs along the way, and ended up getting me ordering a few samples from STC directly.

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Exploring STC MCU Part 2 – So how fast is it?

STC proudly claims that their MCU are fast. And from what I see in their core clock timing table they have a new core design that accelerated the instructions a lot. So how fast is it? Continue reading “Exploring STC MCU Part 2 – So how fast is it?”

Exploring STC MCU Part 1 – The chips

It seem to me that there are some interest in ultra cheap microcontrollers. The Chinese brand STC makes a few 8051-compatible MCU which sells at ridiculously cheap prices.

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Upgrading my old Dell, and fixing the ID chip

I have an old Dell Latitude D620 with Intel Core Duo T2300E processor, 4GB of RAM (aftermarket upgrade kit,) and nVidia Quadro NVS 110M graphics. The machine was sitting in storage for quite a while, but I suddenly I find myself in the need of a Windows-running PC with a real serial port for some maintenance work on my KVM adapter and my managed switch. So I decided to take it out of mothballs and give it somewhat a new life.

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Warning: SSH root password hacking

I am pretty surprised to find out this is happening when I was debugging my L2TP/IPSec tunnel: someone is trying very hard to guess my root password over SSH. A quick check proved to me that my private cloud is under attack too.

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Tutorial: Setting up 6in4 IPv6 on an Ubuntu router

Despite lack of ISP support, I gave myself IPv6 network access by making my router switch IPv6 packets over an 6in4 tunnel. My tunnel provider is Hurricane Electric.

This tutorial is about setting up IPv6 tunnelling and routing, NDP router advertisement and tackling dynamic address. Not all part of this tutorial will fit your needs.

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