Wednesday, January 18, 2017

I love the smell of solder in the morning

I've probably used that title before but it's true. Well I actually don't breath in the stuff but I do enjoy soldering and working with electronics. It brings me back to my electronics background (my first degree and main interest). This weekend I was supposed to go to InfoAge and do a VCF repair workshop to work on my Atari 600xl and my PiDP8. I don't have a working TV setup to hook up the 600xl and the 600xl doesn't have a monitor interface. Which means converters won't work either. So my intention is to first determine that the 600xl works (it does, more later), then add the parts needed and to upgrade it to a monitor interface and improve the video output. I have gathered all my notes together for the 600xl. I did my homework and ordered all the parts so I now have everything I need. I made sure to order the correct parts for the upgrades such as better inductors (beads, lower DC resistance) and the correct sets of resistors to do impedance matching on the video outputs. I've also organized my notes for things like determining the EBC on a transistor (don't be trusting), Color NTSC signal and the 600xl schematics. I worked on the 600xl on Monday night at IXR and found that I had a nice NTSC signal coming off the video out of the 600xl (yea!). Unfortunately the scope was acting up (bump the lead and I'd lose the sync argh). I spent a lot of time with that (I'll need to service that). I also spent the rest of the night discussing Raspberry Pis, Arduinos, MQTT, Node-Red, HA and IoT.

I also started putting together the PiDP8, I didn't exactly start in the correct order. I started with the switches and I probably should have left them until last. Well it might be inconvenient but putting it together won't be impossible. I'm looking forward to having the PiDP8 running and playing Colossal Caverns on it. It's definitely a throwback to my past when I spent my EE programming course playing Colossal Caverns instead of writing BASIC programs. I do recall getting an easy A in the course so I must have done all the work and I recall being constantly interrupted by other students needing help with their programs. I guess I did okay. ;-)

I love the A8 because it was my first computer and my friends and I had them. My first was the Atari 800xl, which I upgraded to 256K DRAM and Omnimon XL. So some time this week I'll fix up the 600xl and modifiy it. I want it running by next week. Then it's time for the DRAM upgrade (16K to 64K), upgrade the ROM to include Omnimon XL and BASIC version C. Then I have a 65C816 and I'll add some more static memory and flash. I want to get a version of Omnimon that will work with the 65C816. This will be a fun side project. But don't expect the 65C816 upgrade for a while. I need to design a nice daughter board to add to the 600xl so I can add the features without damaging the original motherboard.

Friday, December 30, 2016

One last hurrah ... ;-)

Happy New Year folks (yes a bit early) hence the title. As I stated in my last blog post, I've been busy trying to get Pete's esp-mqtt-dev to compile under Linux. It's now working and up on my Github account. I discovered my problem was in the Makefile, an extra backslash (\) at the end of a comment that ate the next few lines (which also had the proper backslashes). Once I fixed that the compiler began to complain (properly) about missing typedefs and declarations. I fixed all of those by adding a lot of typedefs (I need to do some work with stdint.h). There were also a lot of warnings and I'll fix them later. Those are a bit more complex and it's in the cross-compile tool and not Pete's software.

So now I need to break out my ESP8266's and get a few running. I think I have some ESP-01s with 4Mb and ESP-12s 32Mb (yes the little b is bits). I also have the WiFi controlled outlets and the Sonoff inline power controllers (which have the 8Mb chips). I'm not sure I can do OTA upgrades with these smaller chips but at least I can play with the devices until I get the 25Q32 flash chips (32Mb) and replace the smaller chips.

The next steps will be to write my own firmware (using Pete's as an example). I think the first device I build should be something like the BlinkM described on Hackaday. I'd like to see if I can build a device that uses a config manager on MQTT to dynamically configure the device (after it's done it's DHCP). I want this to have as little user intervention as possible. For now it's just a proof of concept. I already have a simple node-red based config mgr working. I guess now it's time to step it up a notch or two.

On the Atari 600xl front, the video cheat didn't work, but it also didn't work on the working 800xl. So that means I'll need to populate and upgrade the existing 600xl video design to the Super Video 2.1XL. I'm putting together my parts list (including 2 50464's RAM chips to upgrade the 600xl to 64K). I expect that the next VCF workshop on January 14th & 15th, I'll be able to work on the Atari video, the SIO2Pi Zero and the PiDP8 (yes, I got one!). Definitely looking forward towards spending time with a soldering iron, scopes, schematics and electronic parts. :-)