Dragon Beta GitHub

[robcfg]

I have a small question about R34 and R35.

Being 0R I guess they are just links, right?

Do I need to connect both? On the populated Beta board picture here, I can see R35 installed, but not R34.

[dublevay]

I'm half way through the Beta board soldering, and would like to know if I can use 4164 ram chips instead of the MK4564N ones.

Yes - I used KM4164 chips originally, although I swapped them out for Phill's modern memory boards afterwards.

Oh, how do I order the tree expansion connector in the middle of the board?

You want these... https://www.aliexpress.com/item/4000215552439.html

For the motherboard it's a straight female. Any expansion cards need right-angled male.

[dublevay]

I have a small question about R34 and R35.

Being 0R I guess they are just links, right?

Do I need to connect both? On the populated Beta board picture here, I can see R35 installed, but not R34.

R35 is 0R (or wire link)
R34 is left open.

[dublevay]

Thanks a lot!

I'm 22 14-pin sockets away of having all sockets installed...

Keep going - sorry I've not been looking in enough. Feel free to email me any questions if I don't reply on here, as am keen to see more of these running!

[robcfg]

Behold!

A fully assembled Dragon Beta board!

I need to make a video cable and probably use my trusty Meanwell PSU to power it. Fingers crossed...

[sixxie]

A fully assembled Dragon Beta board!

Niiiiice. Good luck!

[dublevay]

Behold!

A fully assembled Dragon Beta board!

I need to make a video cable and probably use my trusty Meanwell PSU to power it. Fingers crossed...

Awesome - how did testing go?

[dublevay]

I've only just realised a slight problem with this board as released. Electrically, it is absolutely fine, but for some reason known perhaps only to my mind in another state or a KiCad upgrade, the set of 12 100K resistors to the left of the mouse port are labelled incorrectly. Actually, they are perfectly correct according to the schematic, so whether KiCad or I messed it up, at least it was consistent.

Anyway, the only reason this is slightly important is that for the mouse add-on to work, on the ORIGINAL consecutively numbered board, the ODD resistors needed to be replaced with a wire link or 0R - and not ALL the resistors as I have said in the past. However, due to the renumbering, on these boards, the following resistors should be replaced with 0R:

• R100
• R102
• R103
• R106
• R108
• R109

Basically it's the resistors which are connected to the 7414 chip.