Sporniket's log on hardware stuff

[sporniket]

I have some spare nodeMCU that I ordered to perform the modding of a GBS-8200, so I have some ideas for them.

• a wireless remote control and display for a gotek drive (using a smartphone browser).
• Convert an atari mouse to use an optical mouse sensor.

So, one of them will be plugged to a mouse optical sensor and both will be put into an atari mouse without butchering the socket that lodge the ball. I butchered an unused hp mouse (well, the case has one of its screw engulfed in plastic, totally unserviciable :x ), found the datasheet of the sensor. This is an intermediate/advanced level project, so I plan to do it slowly during 2021.

2020-12-13-project-mouse.jpg

At least I studied a little bit which GPIO pins of the nodeMCU are effectively usable. I am a little bit disappointed on this, other ideas will require an ESP32.

The easy part will be encoding the mouse move by driving xa/xb ya/yb.

[sporniket]

Cannot sleep after waking up during the night, the ideal time to do a little bit of soldering without being bothered by children...

So I devised a little test board so that I will be able to check the gpio output signals of my project involving a microcontroller. The dangling wires are to be connected to the target output gpio. This is basic electronic, and this is my starting point. I devised the circuit and choosed the component values to suit the testing conditions

2021-01-05-test-board-01.jpg

Testing the board, first with high voltage/current (all is powered with a 4,5V battery)...

2021-01-05-test-board-02.jpg

...then with low voltage/current (the string of connected resistors and leds is a remnant of my introductory lesson to LED and resistors I did to my little one - the battery too :D )

2021-01-05-test-board-03.jpg

[sporniket]

• Waiting some IC socket to arrive along my latest order to exxos shop, to finally get started with my H5 builds. Will have to make a complement order to mouser and co to get plccs and other things too.
• Waiting my first experiment with JLCPCB, a custom proto board for the gbscontrol
• Starting more seriously studying VHDL. I found very interesting fpga dev board that I plan to test this year...

The easiest part -and very fun for the software architect me- is just modelizing entities...

starting-vhdl-narrow.png

[sporniket]

I finally took time to test how my new pen display do with my Atari STE. As I expected, it does not support 15kHz. However, I can find a manual setting where the monochrome resolution looks great (in other words : sharp square shaped, uniformly sized pixels). Will have to update the database of screen with that.

2021-02-04--test-new-screen.JPG

[sporniket]

I could work a little on my project of porting to kicad the schematic of the atari STE. Having done the MC68000, I have started to make a proof of concept of the main ICs split into their subgroup of signals, in order to create schematics focused on one subgroup.

In fact, I will go this way for each subgroup of pins of the CPU. The intent is to get small and legible sheets that capture how e.g. the ICs collaborate or share the bus. Ideally I target A5 sized so that printing on A4 makes a sheet with bigger text, and without hundreds of wires crossing over each others.

There will be sheets that will be more traditional too, when this approach is more cumbersome than helpfull.

Anyway, here is the poc in pdf. (I could spot a little bug for one of my symbol on the unit naming, it is fixed on the github release)

poc-ste--2021-02-04.pdf

The experimental libraries of symbols are released here https://github.com/sporniket/retro-comp ... /tag/0.0.2 (unfold the "Assets" if you do not see the *.lib files)

[sporniket]

Messing with Kicad, capturing on the computer the version of the schematic I have come up in relation to my project to replace the ACIAs by an ESP32... I need more preparation, especially ad-hoc footprint/symbol for the connection to the acia. And surely a separate power supply connector to supply current directly from the PSU instead of from the motherboard.

Satisfying in and of itself to reach a tangible milestone (not finished, especially not suitable yet for pcb design, but having done somethings after hours and hours of brainstorming and research, a little sense of accomplishment).

bridge-exp1.png

[stephen_usher]

Just a quick tip on KiCAD and wires...

I've switched to using labels for all the component connections rather than explicit wires. It is/was far too easy to route them badly or get an accidental junction etc. Using labels allows KiCAD to do all the connections for you in the background and if you need to move a connection on a chip it's one move operation rather than deleting wires and re-doing them, which is prone to error.

I've not had one bad wire connection on my boards since I switched.

[sporniket]

Thanks for the tip. It will save me some tedious work on that project.

[sporniket]

Continuing a little on my project of replacing the ACIAs by an ESP32, I reworked the connector using only the pins of the ACIA that are usefull for this project (control and data bus), and generated some symbol after the physical layout of the chips/dev board with my updated script.

Following the tip I received, I revamped the schematic,...

bridge-exp2.png

...continued with pcb design (4 layers with a ground plane and 1 layer unused)...

bridge-exp2-pcb-design.png

...and went up to the 3d preview...

bridge-exp2-pcb-3d.png

Done for the day.

[exxos]

Looking good :thumbup: