QL serial system flaws and fixes

[Dave]

We all know of the QL's notoriously bad serial system.

What's wrong with it?

How could we fix it?

[tofro]

Once we've fixed it, what do we use it for?

(Not meant to be offensive, but I see very rare usage of serial hardware nowadays)

Regards
Tobias

[Dave]

I believe most people who care about serial have it fixed by a Hermes-type solution, so for existing machines, it's dealt with.

I'm just toying with a board that fixes the problems of the Iss. 7 and earlier boards and would be a theoretical design only. I don't think it would ever pass current RF standards if it closely followed the current design. However, having a public, open library of designs for subsystems of the QL will help anyone who wants to address issues in the future, as our brightest people go to new pastures, or sadly die off.

I do have a homebrew 16-bit QL on a breadboard that has mostly working video, but no serial, net, joystick interfaces. I believe it can be improved.

I'm looking for the info so I can make it presentable.

Other areas of interest - this thing has 512K of SRAM, works well. However, it still refreshes the SRAM as this is a hardware function *heh* which is an unnecessary slowdown. For me, the custom logic is a black box. It's an annoyance, but it's just fun tinkering.

Dave

[Derek_Stewart]

Hi,

There was a Serial Port add on board for the QL, made by Terry Harman, which gave a higher throughtput on the serial ports. When I used to have a BBS, this was the thing to have.

But the Superhermes came along and plugged the gap.

I will see if I still have the Harman construction details.

Derek