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Re: QL SD card system....

Posted: Thu May 01, 2014 10:11 pm
by XorA
It certainly looks like hardware was originally designed for 2x 32k or one 64k.

Re: QL SD card system....

Posted: Thu May 01, 2014 11:23 pm
by 1024MAK
The QL Issue 5 schematic lists configurations for:
16k bytes - one 23128 ROM
16k bytes - one 27128 EPROM
16k bytes - two 2764 EPROMs
24k bytes - one 23128 ROM and one 2364 ROM
24k bytes - one 27128 EPROM and one 2764 EPROM
32k bytes - two 23128 ROMs
32k bytes - one 23256 ROM
32k bytes - two 27128 EPROMs

The actual circuit shown on the diagram is for:
48k bytes - one 23256 ROM and one 23128 ROM

But no listing for a 27256 EPROM and one 27128 EPROM (which is possible, as some QLs have this configuration).

Does anyone have a schematic for any of the earlier issue boards?

Mark

Re: QL SD card system....

Posted: Thu May 01, 2014 11:31 pm
by 1024MAK
RWAP wrote:
1024MAK wrote: First, the OS and BASIC were larger than expected. So instead of fitting on one 32k byte chip (or two 16k byte chips), an extra 16k byte chip was needed as a total 48k was needed.
I am never really convinced about this - Tony Tebby also suggests that the Kludge was really an invention by Sinclair to explain away the need for a recall on the basis of a 'software update' rather than an issue with the hardware.

After all, both ROM sockets can happily accept 48K (hence how Minerva fits) and even 64K, which suggests that it was always envisaged that the operating system might be larger than 32K.
Sinclair machines previous to the QL were required to be "feature packed" as Sir Clive wanted maximum features in a limited ROM space. Programmers had to recode and use creative space saving techniques so it all fitted in. The only reason the Spectrum ROM has free space, is because the microdrive code was left out...

Mark

Re: QL SD card system....

Posted: Fri May 02, 2014 7:35 pm
by Simon_Carr
1024MAK wrote:BTW, what issue board is yours?

Mark
1984 Issue 6.... Nothing special.... I think

Re: QL SD card system....

Posted: Sat May 03, 2014 11:01 am
by Luk
I haven't installed the SD card yet. Having read the manual :!: I think it's a good idea to build up the QL_BDI.BIN file first, with the help of Q-emulator. You don't even have to unpack the QL-SD package to do this. Just download the starter pack from Dilwyn's site and follow the instructions. (one remark: the folder for the sd-files is "extensions" and not "extension" as stated in the text).

First impression: the software combined with q-emulator works like a charm. But filling the "harddisk" is no so straightforward. Currently i am wrestling to get the psion progs in their own directory (and make them work there). So still some work to do i guess.

But it's good fun and i hope installing the real stuff soon!

Re: QL SD card system....

Posted: Sat May 03, 2014 3:57 pm
by Paul
Luk wrote:I haven't installed the SD card yet. Having read the manual :!: I think it's a good idea to build up the QL_BDI.BIN file first, with the help of Q-emulator. You don't even have to unpack the QL-SD package to do this. Just download the starter pack from Dilwyn's site and follow the instructions. (one remark: the folder for the sd-files is "extensions" and not "extension" as stated in the text).

First impression: the software combined with q-emulator works like a charm. But filling the "harddisk" is no so straightforward. Currently i am wrestling to get the psion progs in their own directory (and make them work there). So still some work to do i guess.

But it's good fun and i hope installing the real stuff soon!
I hope the SD card I sent you wasn't empty by accident?
Kind regards
Paul

Re: QL SD card system....

Posted: Sat May 03, 2014 5:58 pm
by Luk
No no! SD-card was allright!

When mentioning the downloading of the software, i meant to say that even the unfortunate not-SD-QL-owners can try it out. ;)

Re: QL SD card system....

Posted: Tue May 06, 2014 6:20 pm
by Paul
Before I forget
I have relisted some QL-SD drives
http://www.sellmyretro.com/offer/details/3703
I have changed the postage prices because I found cheaper sending methods.
Kind Regards
Paul

Re: QL SD card system....

Posted: Tue May 06, 2014 6:25 pm
by Dave
My QL-SD arrived this morning.

I just wanted everyone to know that I had a good look at it, and it was well constructed and a very elegant design. If you haven't bought one already, you should get one of the current batch on SMR... :)

I only hope Paul is as happy with his SuperRAM :)

Re: QL SD card system....

Posted: Tue May 06, 2014 6:43 pm
by Paul
Dave wrote:My QL-SD arrived this morning.

I just wanted everyone to know that I had a good look at it, and it was well constructed and a very elegant design. If you haven't bought one already, you should get one of the current batch on SMR... :)

I only hope Paul is as happy with his SuperRAM :)
Thank you very much for the compliments and recommondation.
When I receive my SuperRAM I will also let you know 8-)
Kind regards
Paul