QL Net server to back-up Spectrum files?

[Martin_Head]

Have you tried getting a couple of spare network jack plugs and soldering termination resistors inside them across the connectors (I think 330 ohms).
And then plugging them in the unused Net connectors on the QL and Spectrum. The switches in the jack sockets which connect the termination resistors are very poor. And if the terminations are missing, it can screw up the network connection.

[martyn_hill]

Hi again bwinkel!

You might like to review the attached document as it addresses a number of your latest questions/concerns. Its a bit lengthy, but you should be able to find what you are looking for fairly easily.

Let me know if anything remains unclear having reviewed it - its about time I wrote part-2

M.

[bwinkel67]

Thank you Martin, that is very helpful. The resistor termination is very much like how AppleTalk on a Mac did termination, so it's pretty neat that this would be similar. I still have an old PhoneNet adapter that has an RJ11 plug with a resistor stuck in it...I'll be curious to see what value they used.

There isn't much in the documentation (including termination) but presumably the networking was never explored very much on the QL. I will give that a try and also look at the document you provided. I just want to see if I can make a connection now that I own an Interface-1. I do have a Q68, which I will also wire up, but to get two early 80's computers to connect would be cool.

I need to find a way to attach to my name (Mike) to my handle (the way Discord allows you to change it) as it's always funny when people use bwinkel to address me

[martyn_hill]

Aha! So it's 'Mike'!

[tofro]

I need to find a way to attach to my name (Mike) to my handle (the way Discord allows you to change it) as it's always funny when people use bwinkel to address me

The simplest thing is to sign your messages with your name.

Tobias

[bwinkel67]

So I tried a few more times today to get the QL and Spectrum to talk to each other. I repeated what I did previously, plus followed some of the samples in Martyn's document.

When using TK2.23, copying from QL to Spectrum, I get a "Net aborted" error. Without TK2, I get no errors (still doesn't do anything though). I cleaned all the contacts on both device's connectors with isopropyl and a cut-down swab, but that didn't help. I do notice that the load screen on the Spectrum does change when I start copying from the QL, but nothing seems to happen.

Here' s what I tried...note that in both examples, I set the network IDs for both computers first, then do the rest:


Copy a file from QL to Spectrum, with Spectrum monitoring for QL network ID to print what it gets from the network onto the display. My expectation here is that the BASIC boot program from the QL would display on the Spectrum's screen.

Spectrum

Code: Select all

FORMAT "n";10
OPEN #4;"n";20
10 PRINT INKEY$#4;: GO TO 10
RUN

QL

Code: Select all

net 20
copy_n mdv3_boot to neto_10

Use the example from Martyn's document. I'm not sure what LOAD *"n";20 SCREEN$ is supposed to do. What is SCREEN$ on the Spectrum? Is it similar to con_ on the QL?

Spectrum

Code: Select all

FORMAT "n";10
LOAD *"n";20 SCREEN$

QL

Code: Select all

net 20
copy_n mdv3_boot to neto_10

One thought I had...I have a US QL. Could its faster crystal screw up networking?

The next thing to try is build the connectors for the Q68 and see if I can get the Spectrum to talk to it.

[dex]

SCREEN$ in this case is replacement of CODE 16384,6912, which means exactly the memory area of VideoRAM.

[martyn_hill]

Hi Mike

Given your experience so far, it looks like your next step would be to modify your copy of the TK2 ROM, burn it to a fresh EPROM and try again.

If you can tell me which version of TK2 you are running, I can work out the offsets of the hardcoded timing constants in that ROM version and send you a modified image ready for burning.

Let me know if you'd like to try that approach.

Alternatively, due to the more refined timing available to the faster CPU/FPGA of the Q68, it is likely to work without modification. The Net driver for the Q68 (v3.05) can be found on Dilwyn's excellent site and, yes, would just require the additional passive components fitted to the Q68 to allow the connection.

Martyn.

[bwinkel67]

Hi Martyn,

Yes, I'd like to burn a new TK2, I can easily burn one. My version says TK2.23.

So the 60Hz US vs 50Hz UK shouldn't be an issue, or is adding to my difficulty?

Mike

[martyn_hill]

Hi Mike

Ok, I'll lookup those offsets and get back to you with the details sometime tomorrow.

If I remember correctly, the US QL had a very slightly different main 15MHz crystal/frequency, but I doubt it would make the difference between a working and non-working Network all on its own...

Knowing where to patch the TK2 ROM could help you in that regard too, but we'll soon know.

Stand-by...