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Mikorians
June 17th, 2014, 11:52 AM
Aw. I LOVE my XT-CF-IDE.
I'd pay what I just paid to get an FDC.
It's a shame they didn't combine these two at least...
No more boot issues ever again...

Maverick1978
June 17th, 2014, 12:22 PM
Combining cards makes the design much more difficult, increases the PCB manufacturing cost, and potentially, increases the build cost and/or complexity (as remaining with thorugh-hole, discrete components means more of them, so more cost, and if we went with surface-mount, now the build complexity is higher, eliminating many hobbyist builders)

With that said... Sergey designed and built an FDC/serial controller which is a nice companion piece to the XT-IDE family of cards. Read about it here. (http://www.malinov.com/Home/sergeys-projects/isa-fdc-and-uart)

We also had a thread going about a 4-drive FDC, but I dont recall that ever coming to fruition.

Chuck(G)
June 17th, 2014, 12:39 PM
It did come to fruition--I have one here. I don't know what the interest ended up being, however.

If you don't mind working in "360K" density, there were several Taiwanese manufacturers who made FDC, clock, serial+parallel boards for the XT crowd. Maybe one will turn up.

SomeGuy
June 17th, 2014, 12:56 PM
If you are patient enough, every now and then an original 8-bit 1.44mb controller like the DTK PII-151 or Magitronic B215 turns up. They tend to sell for around 50 or 60 dollars.

Here is one on ebay right now: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=360940783775#ht_2168wt_1282

sergey
June 17th, 2014, 01:09 PM
Combining cards makes the design much more difficult, increases the PCB manufacturing cost, and potentially, increases the build cost and/or complexity (as remaining with thorugh-hole, discrete components means more of them, so more cost, and if we went with surface-mount, now the build complexity is higher, eliminating many hobbyist builders)

With that said... Sergey designed and built an FDC/serial controller which is a nice companion piece to the XT-IDE family of cards. Read about it here. (http://www.malinov.com/Home/sergeys-projects/isa-fdc-and-uart)


Todd Goodman has PCBs in case you want to build FDC controller:
https://groups.google.com/forum/#!topic/N8VEM/EkVvYDdg9Xg

It is not difficult to combine XT-CF-Lite, FDC and serial on one board. It might be even possible to save an EPROM (use a single 32 KiB EPROM for both XT-IDE and FDC BIOS extensions). I was toying with this idea, and I even have a sketch somewhere. But I was skeptical about popularity of such board: some people like to have only XT-CF-Lite, some only FDC. But if there is an interest I can revive that project. Maybe add some SRAM too - for extending older PC memory to 640 KiB and beyond (for UMBs)?!

Krille
June 17th, 2014, 05:30 PM
No more boot issues ever again...

In case you are not aware, since you are using XTIDE Universal BIOS, you can boot from emulated floppy drives or harddrives over a serial connection (http://code.google.com/p/xtideuniversalbios/wiki/SerialDrives).

Maverick1978
June 18th, 2014, 07:16 AM
It did come to fruition--I have one here. I don't know what the interest ended up being, however.
Huh - I must've missed it. I was certainly interested in a 4-drive FDC. I'll have to dredge up the old thread - I didnt realize that it had went beyond the alpha design phase after Sergey released his board.

modem7
June 18th, 2014, 11:31 PM
Huh - I must've missed it. I was certainly interested in a 4-drive FDC. I'll have to dredge up the old thread - I didnt realize that it had went beyond the alpha design phase after Sergey released his board.
The 'converted' VCWiki topic is at http://www.vintage-computer.com/vcforum/showthread.php?32476
It has pointers to the development/testing threads. Last activity is about 6 months ago (people seeking boards).

Mikorians
June 19th, 2014, 10:24 AM
Alas, unlike the CF HDD,
This is only a controller (GREAT, don't get me wrong),
'Tisn't an emulator.
I noticed the serial boot option, but implementation escapes me.
It might've been nicer if a boot formatting tool had been on the rom instead, but I'm sure nobody could settle on which version of DOS it should be, although--
Since the CF drive is so Ginormous, maybe the LAST version...?

pearce_jj
June 19th, 2014, 11:57 AM
There might be some mileage in that idea, at least including an optional ROM disk the XTIDE Universal BIOS. Actually I think that might have been implemented already with the JR-IDE card, thinking about it.

Mikorians
June 19th, 2014, 12:13 PM
I'm not sure what to think of a ROM disk...
But there's a unit I've been thinking of:
http://hxc2001.free.fr
Sells it. (I haven't bought one yet)
The SD card version seems to be best because
It allows read AND write to disk images.
I spoke with the guy, Jeff, and he says it supports 360K 5150 compatible disk images.
Unlike other emulators that have no docs, they seem to.
I've had to buy a controller card to use it with.
(Thank you, fellow member)

Sergei- Yeah, EMS, and I remember someone posted the idea of adding a sound card to the mix!
It wouldn't have to BE the actual OPL chip, just ACT like one. Many chipsets for other Mobo's had the Realtek chips...
Add more into the EPROM window to control all of the features, and you'd have 'the golden fleece', heh!
Having made a few circuits in my time, it's important to have a UNIFIED BIOS, to avoid incompatibility and standardize things.

Krille
June 21st, 2014, 03:53 PM
Alas, unlike the CF HDD,
This is only a controller (GREAT, don't get me wrong),
'Tisn't an emulator.
I noticed the serial boot option, but implementation escapes me.
It might've been nicer if a boot formatting tool had been on the rom instead, but I'm sure nobody could settle on which version of DOS it should be, although--
Since the CF drive is so Ginormous, maybe the LAST version...?

I linked to a document that explains how to use it. What more do you need to know? The big selling point of this feature is that you don't need a working floppy drive and floppy to boot an operating system (and presumably, install it to your harddrive).

Mikorians
June 21st, 2014, 04:18 PM
Krille, I read the blue text link, and thanks!
That explains everything I'd need in a boot emergency!
I appreciate it.

Caluser2000
June 21st, 2014, 05:46 PM
If you ever want to use a high density fdd another option is using a generic 16 bit mutli i/o card. A few folk here have done this on their XTs https://sites.google.com/site/misterzeropage/ Some Dos variants, for example DrDos 7.x, don't need a helper file and will boot off high density fdds.

offensive_Jerk
June 21st, 2014, 06:21 PM
Do you need an 8-bit high-density floppy controller? I just tested a couple in my 5150 board and they were able to boot dos on a 1.44 floppy.

Mikorians
June 21st, 2014, 07:06 PM
Wow.
That's real tempting, but I wound up with a standard density one.
How much did you want?
I probably can't afford it.

Do you guys mean a REAL 3.5" will boot on a 5150-
With no trouble whatsoever?
If the card has a special bios is there a danger of interference between
It and the nice VGA card or my XT-IDE card at c800 or my new sound blaster 2.0?
(Trying to build a real hot-rod here)

offensive_Jerk
June 21st, 2014, 08:09 PM
I have a video if my 5150 motherboard booting a 3.5 1.44mb floppy of dos, with my other VGA card I have installed. I'm not positive it won't conflict with your other VGA card I traded you previously though. I don't know what address spaces these cards use.

Anyone chime in with about how much a 1.44 8bit floppy controller goes for ?


EDIT: it booted IBM PC dos 3.2. Now that I think about it, that might've a 720k distribution. I'll check later if it is a 1.44 or 720k disk.

modem7
June 21st, 2014, 09:13 PM
If the card has a special bios is there a danger of interference between
It and the nice VGA card or my XT-IDE card at c800 or my new sound blaster 2.0?
With your IBM 5150, there will always be a possibility of conflicting resources (RAM address, ROM address, interrupt, DMA channel, I/O address) when you go to add a card.
Where I used to work, we would often stick a piece of paper, inside the case, that told us what resources that the existing cards were using.
It saved significant time down the track.
Example:


RAM ROM INT DMA I/O
---------------------------------------------------
Card XXXX: None C800-CA00 5 3 320-32F
Card YYYY: None None None None 201


Coupled with that, you also had to take into consideration what resources the motherboard was using.

Mikorians
June 22nd, 2014, 08:43 AM
Nods.
Mm hm, helpful, helpful.
:)

offensive_Jerk
June 22nd, 2014, 02:02 PM
So the dos disk I was using to boot wAs a 720k disk. Crap. I just grabbed the first 3.5 disk I saw. Now I'll have to retest and make sure I use a 1.44mb disk this time.