Need help reverse engineering Timex Store Demonstrator ROM file

[dessony]

XavSnap,

As I viewed one of your recent gifs, I noticed there is enough headroom which satisfied me. I definitely would order PCBs after the edge connector's slightly enlarged holes mentioned by you, XavSnap, in the Kicad/Gerber file.

I take care of the DC-DC converter's position.

I also want a "fingerboard" in addition to an edge connector with its wire wrapping tails. It is for more interfaces, modules, or peripherals hooked up to the computer.

Thank you very much in advance.

Cheers,
DesSony

[XavSnap]

Hi,

My homemade rear connector:

Gerber_extension.zip

(11.4 KiB) Downloaded 278 times

Back_Ext_Kicad.zip

(259.73 KiB) Downloaded 329 times

ZX81_BUS_Connector.zip

(77.08 KiB) Downloaded 293 times

[XavSnap]

Hi,

The issue 2.1 gerber seem ok.
Connector pin hole 35 mils.
Eprom ZIF move to the top of PCB.

StoreDemo_v21_Gerber.zip :
http://zx81.ordi5.free.fr/CartesZx81/Ti ... onstrator/

[dessony]

Hi, all of you,

The PCB order has already been placed for StoreDemo_V21(5) and Extension(10). I expect a package before November 1st.

Cheers,
DesSony

[XavSnap]

It is'nt really a problem, but the TRACO can be lying to get some space.

[dessony]

XavSnap,

Yes, the TRACO will work with its long body laying down flat. Expect to add three little copper wires to the converter's legs. Or, I would put a DC-DC converter on the other side of the particular board and match the converter's dot to the board's 9vdc hole.

Cheers,
DesSony

[dessony]

XavSnap and the rest of you,

I just received the Timex Store Demonstrator board, issue 2.1 reversion today (10/27/'22), and an extension board from a carrier.

I tested the board with a continuity probe, which was designed for testing the electric water heater, for the voltage feed. The ICs' V+ and GND point areas expectedly passed a test! Huge two thumbs up!

I also noticed nothing shiny area around the two "tabs" on the left lower side of the board. I will post a picture here a little bit later.

A PCB fabricator decided to add a 1-millimeter "space" cut around the tab and board edges after their technical advice with me. I went for it.

I am waiting for a PCB edge connector's arrival.

Regards,
DesSony

[XavSnap]

I also noticed nothing shiny area around the two "tabs" on the left lower side of the board. I will post a picture here a little bit later.

A PCB fabricator decided to add a 1-millimeter "space" cut around the tab and board edges after their technical advice with me. I went for it.

Ok.
If you add 1mm on the hedge cut, the removable tabs (feet to place at the bottom of the card) will be ignored!
I don't know the CNC cutting size...

In fact, they ask you to abort the inside board cuts. The cutting width was less than 2mm (1mm+1mm between both edge-cut ) !
May be a technical problem from the PCB fabricator...

It can be cut with a good drimel disk.

annoyingly, the cut width seems to be 1mm for the CNC !

[dessony]

XavSnap and the rest of you,

Here are the photos I promised!

"The Board"

Tabs area

Cheers,
DesSony

[dessony]

XavSnap and the rest of you,

The board is still a no go for a direct connection! Unless you continue to use a printer connector with the particular board. Look at the zipped folder of pictures. I used some tape to simulate temporary soldering. Please add a centimeter and a millimeter (11mm) to the height side of the board, between the card edge connector's top side and a 74LS244 socket's bottom side.

T S Demo _2_1.zip

(10.34 MiB) Downloaded 286 times

Plus, I had to squeeze the horizontal part of the pins of the card edge connector to set the connector onto the board. Please check the card edge connector's specifications and adjust the edge connector's row spacing spec. within your Kicad ZX81 share zone file. Row Spacing .200(5.08)
https://www.mouser.com/datasheet/2/123/ ... 399220.pdf

Don't forget to add some metal sections to the two tabs' areas.

Be a little generous on the extension board's card side. Make these "fingers" 1 centimeter instead of 6.5 millimeters. And apply it to the Kicad ZX81 share zone.

Thank you very much in advance.

Regrads,
DesSony