In an earlier post, I described how I was parsing commands input (via serial) into the Zolatron 64 8-bit homebrew computer in assembly language. That parsing process matched an input command with an internal list and the result was a ‘token’, a single integer value of $80 or more representing that command that is placed in a memory location. Or… Read more »
Okay, so this is going to be a long one. Grab a coffee, settle down and we’ll begin… The last time we talked, I was able to send messages to the Zolatron 64 6502 homebrew computer via its serial port. But all it could do was print those messages to the LCD screen. It’s time to actually do something with… Read more »
Early on in the design of the Zolatron 64 6502-based homebrew computer I made the decision that I wasn’t going to bother with attaching a keyboard and monitor. It has a 16×2 LCD display for small stuff. Otherwise, I/O was always going to be via serial. That means talking to the machine via some kind of terminal software. To date,… Read more »
Many thanks to reader Michael McLaren for giving me a heads-up about a better way to move the cursor on the LCD display. In an earlier post, I described how I was using the ‘shift cursor right’ command multiple times to put the cursor in the desired position – mainly so that I could use the second line of the… Read more »
One thing it was obvious I would want to do with the Zolatron 64 6502 homebrew computer is have a routine to display the contents of sections of memory – à la Wozmon. There’s a snag, though. The content of any given byte in memory is a number, in the range 0-255. But to display this on the screen, this… Read more »
A quick recap. The Zolatron 64 6502 homebrew machine is at the point where it can print messages to an LCD screen and send and receive messages via the serial port. Most of the time. The incoming messages are put in a buffer and then printed to the LCD. And a fat lot of use that is. I wanted to… Read more »
Listening is so much harder than talking, don’t you think? That’s how it turned out with the Zolatron’s serial port, anyhow. Getting the computer to send messages was pretty easy. Receiving them? Not so much. The first stages of developing the software were typical. I wrote code that I knew should work. It didn’t. I cursed the binary gods for… Read more »
It didn’t work. Not straight away, anyhow. Once I’d wired up the 6551 ACIA chip, my UART of choice to give the Zolatron 64 a serial port, I threw together some code to test it. It was pretty simple – it took my already known-good code that prints a message to the LCD and added to that a routine to… Read more »
So far, the Zolatron 64 6502-based homebrew computer has output (a 16×2 LCD screen) but nothing in the way of input. I have toyed with the idea of getting it to output to, say, HDMI using a Teensy as an intermediary. And also of giving it a PS/2 keyboard input (the latter still being a possibility). But in the end… Read more »
Every Raspberry Pi deserves protection. Having used these boards since the first iteration, I have tried many cases over the years, all of them with their strengths and weaknesses. Now I’ve settled on a couple of firm favourites – both from Argon40. And to get this out of the way up-front, this post is not sponsored in any way. I’m… Read more »
It seemed like a good idea at the time. The TTGO ESP32 microcontroller board that I’m using for a room thermometer project comes with a battery connect and charging circuitry for a Li-Ion cell. It would be so much easier to deploy the thermometer if I could run it off a battery. And it works. Kinda. There are issues, though…. Read more »
My previous method of logging the CPU temperatures of machines on the network involved a Bash script sending out a message via MQTT. This was intercepted and logged by a Python script running on a server, which wrote the data to text files in a place where the intranet server could see them. Phew! It’s a miracle it worked. But… Read more »
A while back, I made a couple of ESP8266-based room thermometers. These have been beavering away happily ever since – one on the desk in my office and one in the living room (or salon as we say in France). The only significant change I’ve made to them is to add the capability for them to report temperatures to an… Read more »
It’s always a good idea to know the state of the machines on your network. Plus, I’m a geek, and messing around with data appeals to me. One metric I especially like to keep an eye on is CPU temperature. Why? Why not? I’ve recently got into InfluxDB and Grafana, and that’s the way all future projects will be going…. Read more »
Just lately I’ve been getting into home automation. No, not with ESP8266s and lots of soldering and programming – that comes next. I mean the easy way, by buying smart lightbulbs and switches. We have an old, dark house, which means we use a lot of lamps. Every morning, in the living room alone, we’d go around switching on seven… Read more »