QL Net server to back-up Spectrum files?

[Andrew]

What is the machine under the monitor?

Looks like an Atari TT030

[vanpeebles]

Good knowledge

[stephen_usher]

Post of the month right there!

What is the machine under the monitor?

It's an Atari TT.

[Chr$]

Sorry to bring this up again. Not QL related as such but I've just been playing around with a vDrive ZX (I love the fact that the commands are almost the same as the QL).

I was going to use the 'copier' program from the intro cart that comes with the IF1 to copy stuff on to new virtual drives, but neither of my intro carts do much and I can't get the copier program to load.

Does anyone have or know where I can get the intro cart as an mdr file? I've tried other md copier programs but they seem to default to copy from drive 1 (which is a vDrive) to drive 2, which isn't any good - or they screw up the extra vDrive commands.

[Chr$]

Forget I said anything! Found it here:

http://www.worldofspectrum.org/infoseek ... id=0014770

[bwinkel67]

- The different QL Issue boards can have an impact here, as much as it does between QLs (v6 or v7 being more reliable.)

Came across this old post. Will soon be trying to connect the ZX Interface 1 to my QL. I have a US Samsung model. What board issue range would that fall under? If I recall correctly, I believe mine says Issue 5, though according to Urs (one of his videos on different models) the US numbering was different. I got a bit confused on what he was saying in how it related to the normal numbering system.

I guess once I try the connection I'll see how reliable it is, but was curious if the US Samsung boards are considered to fall under the more reliable with regard to networking. Also, how does the Hermes chip fit in? I believe it handles serial and microdrives communication, but does it also handle networking or is that done elsewhere?

[martyn_hill]

Hi there!

As far as reliability transferring from a Spectrum to QL is concerned, the options available to improve this depend upon a number of factors and your willingness/time to tinker... Here's what I've found so far that may help guide you:

The primary issue is a very subtle bug in (both versions of) the Int-1 Shadow ROM. Due to the clever way the Int-1 ULA manages the timing of the START Bit when receiving packets, the issue doesn't seem to bother Spectrum to Spectrum comms, but only when the QL is receiving packets from the Spectrum (the QL uses an entirely SW method to detect the START Bit, with no hardware assistance from the QL's 8302 ULA)

Due to the faster CPU available to (S)GC equipped QLs, or the QXL, you can already get fairly reliable comms with the Spectrum, though the root cause is still present and does break the odd packet transfer - most users of those platforms haven't noticed it yet

A. The best fix here is to update the Int-1 ROM with a patch that I have developed to address the bug (plus a couple of other less impactful bugs), but that is tedious to achieve - to put it mildly.

B. With the TK2 ROM in place on your BBQL, there are a couple of timing constants that can be adjusted that go 75% of the way to allow proper receipt of packets from an unmod-ded Int-1/Spectrum. If you can tell me the TK2 ROM version you use, I can work out and share with you which bytes need patching, BUT you'd then need to burn a fresh TK ROM image AND the patching tends to break QL comms with other QLs (unless you also adjust them in a similar way.) Technically, a similar patching could be made to QDOS itself if you do not have TK2, but the way the Net code is designed in QDOS itself makes it a little less straightforward to tweak than in TK2. Also, I'd argue that any actual productive work with a QL requires at least TK2 - and that is especially true with Networking.

C. The inconsistent timing of Iss-5 QLs when accessing the 8302 ULA further exacerbate the issue, though this factor is less impactful. If you remain unsure whether or not your US QL is really an Iss-5, the thing to look for is whether you have a 20-pin HAL IC installed next to the 8302 ULA, or just a couple of 7400 series ICs. The HAL is part of how Sinclair 'moved' the 8302 from inside the contended video-memory bus direct on to the CPU bus, thus avoiding the access-time inconsistency that can otherwise upset the network bit-banging code.

Happy to dive in more deeply once you decide how much time you're willing to devote to the project and which of the above two options is more accessible to you...

All that said, you might just be lucky and find it works fine without any of the above (and I'd be REALLY interested to hear about it!)

As for your question about the IPC/8049 - no, it has no connection to either MDV or NET handling, and only manages KB, Sound and SERial (receive.)

[bwinkel67]

I will be experimenting with it tomorrow so will see if I am in luck or have it not work. Since I normally use ICE/MICE, I usually load TK2 via a bin file from my vDrive...does that make it easier to patch, or does that not make it work at all? I can also easily burn a new TK2 as I have a spare ROM cartridge that I can stick an EPROM on (that's how I use TK2 when I need to reboot alot).

I'm guessing the Int-1 ROM replacement isn't just plugging in a newly burned EPROM using a TL866ii+ (which I have), but instead having to either require a special burner or some mods on the board (similar to getting an EPROM to replace the ROM on a Spectrum 48K)?

[martyn_hill]

Hi again!

TK2 loaded in to RAM will not support the network (though almost/all other features work as per the ROM version) - the Net code requires consistent timing so must run in ROM on the BBQL.

And yes, replacing the masked 8kb ROM with a programmable equivalent in the Int-1 is a feat of engineering in itself and not for the faint of heart. If you wanted to explore this, I can outline the steps, but given that you could go the QL ROM patching route, I'd suggest that instead...

Whilst I make no claim on the Int-1 patches that I devised and would be more than happy to share them, my current EPROM image is actually built on Ian Collier's version (it's a great mod in itself) and I haven't been able to contact Ian as yet to ask if he'd mind me sharing my Network patch adjustments to his ROM image. I could extract my changes to be fit for the original Int-1 ROM (v2 is the best of the original versions), but it's an effort I wouldn't get around to for a little while...

[bwinkel67]

I didn't have much luck today. With a BBQL I got no connection. Then plugging in TK2 ROM (likely I got it from Dilwyn's site) also had no impact. Here is what I tried for both:

On QL:

Code: Select all

net 20
copy neti_10 to con

On Spectrum/Int-1

Code: Select all

10 format "n";10
20 open #5;"n";20
30 print #5;"a";
40 go to 30
 

...and nothing. I also went into the other direction and tried copying a file to neto_10 and having the spectrum look for it via INKEY$, and nothing. Also tried saving and loading and nothing. It seems that the Int-1 is just waiting for the QL.

Maybe the user guide for the QL I was using was wrong (some PDF of the original that was OCR'ed and had tons of weird spellings). I would have expected the "a" character to appear on the console window of the QL. Note that I used a mono network lead...I assume it's not supposed to be stereo, right?

I tried both ports on the QL and the Spectrum. Neither side ever gave an error, but I don't suspect I should. Note I used Andrew Pennell's ZX Microdrive book for the Spectrum network commands.