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General Category => NC100, NC200, PCW, PDA600 - the rest of the Family! => Topic started by: chinnyhill10 on 22:42, 14 February 16

Title: PC 2086/30 - What type of hard disk interface?
Post by: chinnyhill10 on 22:42, 14 February 16
Given up on trying to capture from the PPC640. The digital CGA signals have proved too painful to convert and capture. So I've been keeping an eye out for a later Amstrad PC that has a VGA card so has something more "analogue".


So this evening I've won a PC2086 on Ebay. I note it comes with a 30 meg hard disk. Does anyone know anything about the interface card?


Is it some oddball Amstrad thing or is it a standard IDE 8 bit card? I.e can I plug a Compact Flash adapter into it and use that as a hard disk?


At the end of the day, floppy will be fine for me. But would be an interesting mod to get a CF card into it when it arrives.


Anyone know?


Cheers.
Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: Bryce on 22:51, 14 February 16
The PC2086 has an RLL Hard drive (I think that stood for Run Lenght Limited). Not sure if it was MFM RLL or one of the weirder ones, but it's definitely not IDE.

What was the issue with the CGA? A CGA to SCART adapter is very easy to put together.

Bryce.
Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: SRS on 22:57, 14 February 16
RLL Disc  -> but has 8bit ISA Ports (Standard XT)

Amstrad PC2086 - computers.popcorn.cx (http://computers.popcorn.cx/amstrad/pc2086/)

To replace drive see: Replacing the PC2086 hard drive (http://www.seasip.info/AmstradXT/scsihd.html)
Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: chinnyhill10 on 23:42, 14 February 16
Quote from: Bryce on 22:51, 14 February 16
The PC2086 has an RLL Hard drive (I think that stood for Run Lenght Limited). Not sure if it was MFM RLL or one of the weirder ones, but it's definitely not IDE.

What was the issue with the CGA? A CGA to SCART adapter is very easy to put together.

Bryce.


Struggled with a GBS board as it turns out despite what the documentation says it doesn't work with all CGA, just the analogue type.


Looked at CGA to SCART circuits but the big issue is accurate colour reproduction. No point building a circuit if the colours end up wrong. If you want to do it properly you need a far more complex circuit. There is one ready built available from the USA but the person who was going to sell me one went AWOL.


The other advantage of the 2086 is it will let me use EGA and VGA stuff as well. But mainly the EGA stuff interests me most.
Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: chinnyhill10 on 23:44, 14 February 16
Quote from: SRS on 22:57, 14 February 16
RLL Disc  -> but has 8bit ISA Ports (Standard XT)

Amstrad PC2086 - computers.popcorn.cx (http://computers.popcorn.cx/amstrad/pc2086/)

To replace drive see: Replacing the PC2086 hard drive (http://www.seasip.info/AmstradXT/scsihd.html)


That talks about SCSI, not IDE.


HD isn't the end of the world. Just had a sudden thought it might be a nice addition. Of course if I can get hold of an 8 bit IDA card then a CF adaptor would then be a goer.
Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: GeoffB17 on 23:55, 14 February 16
Don't know if it's still an issue..


I saw a reference to the 2086 using a HD interface that was 'compatible with XT IDE'.


Also, the reference to RLL is actually about the coding of the data.   So RLL is a variety of MFM (as in a variety more suitable to HDs).   Not, I think, anything to do with the electrical/signal interface.   I think it allows more bits to be packed into the same space.


Geoff
Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: Bryce on 00:02, 15 February 16
MFM and RLL used a 34 and 20 pin connector and it isn't IDE compatible.

Bryce.
Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: Bruce Abbott on 05:45, 15 February 16
IIRC it was a 30MB RLL drive with Western Digital controller (ST-506 (https://en.wikipedia.org/wiki/ST-506) interface).

Replace it with this:-

XT IDE disk controller - DP (http://dangerousprototypes.com/docs/XT_IDE_disk_controller)
Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: Bryce on 10:02, 15 February 16
Or build yourself one of these:
XT-CF-lite rev.2 - lo-tech.co.uk (https://www.lo-tech.co.uk/wiki/XT-CF-lite_rev.2)
lo-tech ยป XT-CF-lite rev.2 PCB (https://www.lo-tech.co.uk/product/xt-cf-lite-rev-2-pcb/)
and use a CF Card.

Bryce.
Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: Bryce on 15:06, 21 February 16
Here's what the Lo-Tech XT-CF looks like when it's finished. I just built this one for one of our members here. The PCB quality is top. However, this isn't a project for anyone who's just starting out in electronics/soldering, the designer went of 0603 parts although there's loads of space on the PCB and soldering a CF socket also isn't exactly a walk in the park.

Bryce.

Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: chinnyhill10 on 15:11, 21 February 16
Looks interesting, but as a Gotek is only 12 quid these days and apparently the computer supports 1.44 floppies, I might as well go with that.

Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: Bryce on 15:55, 21 February 16
Well, it's up to the user, but there is quite a bit of PC software that won't load from a floppy. And a Gotek can't come close to having a real harddrive on the PC. This isn't a floppy emulator, it's a harddrive.

Bryce.
Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: chinnyhill10 on 16:40, 21 February 16
Quote from: Bryce on 15:55, 21 February 16
Well, it's up to the user, but there is quite a bit of PC software that won't load from a floppy.


Not many games of interest that I can see that would be of use on the lowly 8086 processor. Every game I've tried from floppy has been fine.


By the time you get to the stage hard disk becomes a requirement, you need a 286 processor anyway In fact even Outrun in EGA runs like a dog on the machine.
Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: Bryce on 16:44, 21 February 16
I can't really comment on 8086 gaming, I don't have an 8086 and back when I did have one it was blazingly fast because there was nothing better at the time. Eitherway, the member who asked me to build this obviously thinks it's good to have :)

Bryce.
Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: MaV on 19:09, 21 February 16
I had an XT back in the days, and gaming without a hard disk was a nightmare. i thought a two disk drive system was enough, but acquired a hard disk not so long after realising how tedious disk swapping was.
The 5 1/4 inch disks had 360k. Format it with DOS, and there's not a lot left for a game, and having a separate boot and game disk meant a lot of disk swapping.
The DOS games around '88/'89 didn't target the XT, that is true. Nevertheless most of them did run, even if a bit sluggish.
But try the typical adventure or roleplaying games of that era, and you'll be in for a lot of disks to handle (pool of radiance had about 5 I think; plus you had to save on a separate disk, the original ones being full to the brink with data.)
Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: KaosOverride on 19:26, 21 February 16
I have bot the xt-ide cf 8 bit and the 16 to 8 bit one for standard ide drives.

Both work with the same universal xt bios. Great pieces of hardware.

Also I have the original pc2086 xt controller and just a rom replace with the xt universal chip works. Sure that with some retracing can be reworked to work with some cf.

But some pc2086 came with the same controller than pc1640, the 20/32mb ones, I have the later 8bit ide 40Mb.

Also consider a NEC  V30 upgrade for CPU!! Gives a little boost and gives some compatibility with few 286 software that actually is for 80186... Someone compiled Wolfestein 3d for 8086 and V30 and he last one is more fluid, but also slow...
Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: chinnyhill10 on 21:43, 21 February 16
Quote from: MaV on 19:09, 21 February 16
I had an XT back in the days, and gaming without a hard disk was a nightmare. i thought a two disk drive system was enough, but acquired a hard disk not so long after realising how tedious disk swapping was.
The 5 1/4 inch disks had 360k. Format it with DOS, and there's not a lot left for a game, and having a separate boot and game disk meant a lot of disk swapping.


The PC2086 comes with 720k 3.5 inch as standard and the controller supports 1.44 disks.
Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: chinnyhill10 on 21:50, 21 February 16
Quote from: KaosOverride on 19:26, 21 February 16


Also consider a NEC  V30 upgrade for CPU!! Gives a little boost and gives some compatibility with few 286 software that actually is for 80186... Someone compiled Wolfestein 3d for 8086 and V30 and he last one is more fluid, but also slow...


Just ordered up a V30 as it was only 10 quid. Will see what improvement it brings.
Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: MaV on 10:34, 22 February 16
Quote from: chinnyhill10 on 21:43, 21 February 16The PC2086 comes with 720k 3.5 inch as standard and the controller supports 1.44 disks.
720k (and 1.2mb 5 1/4" was standard for AT), and 1.44 for an XT computer was highly unusual at the time. So, that's good to have.
But it won't alleviate the problem you'll have with bigger games that came on three to four disks of that size (plus the need for a boot disk).
A hard drive does pay off.

A V30 (or V20 for an 8088) will improve the speed by about 20% in general. It is noticeable.
Title: Re: PC 2086/30 - What type of hard disk interface?
Post by: chinnyhill10 on 23:54, 25 February 16
Quote from: MaV on 10:34, 22 February 16

A V30 (or V20 for an 8088) will improve the speed by about 20% in general. It is noticeable.


The V30 is now in. Found a company in the Netherlands selling them as new stock.


Located the socket. Positioning of chip made it hard to get the 8086 out. Then had to carefully bend pins of V30 to get it into the slot. The new chips pins were just a bit too wide.


I powered on and she works fine. And yes the speed increase seems to be about 20%. Well worthwhile!


If anyone else is interested the seller still has 2 chips left:


1 PC. NEC uPD70116C-8 V30 16/8-bit CPU / MPU D70116C-8 D70116 | eBay (http://www.ebay.co.uk/itm/220928607823)
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