FDC Chip information needed
KDMcCullum
package. I know this is a bit vague but I am putting together a Z80 system from
scratch and I have been looking for a FDC chip which I can use. I hope to get
CP/M running on this thing. Most of the SMC chips are QPF chips which I can't
work with. In searching for a controller I can work with I have found that many
of the 40 pin DIP chips (Z0765A08, uPD765, 37C65CP) have been discontinued.
Sombody must know of a manufacturer still supplying a DIP packaged chip.
Thanks to everybody who helped with the memory mapper question. I'm still
looking for spec sheets but at least I've got a start.
Kurt McCullum
en...@numerik.math.uni-siegen.de
: I'm looking for some spec sheets for a floppy disk controller chip in a DIP
: package. I know this is a bit vague but I am putting together a Z80 system
: from scratch and I have been looking for a FDC chip which I can use. I hope
: to get CP/M running on this thing. Most of the SMC chips are QPF chips which
: I can't work with. In searching for a controller I can work with I have
: found that many of the 40 pin DIP chips (Z0765A08, uPD765, 37C65CP) have
: been discontinued.
Uh, that's sad :-(.
: Sombody must know of a manufacturer still supplying a DIP packaged chip.
IIRC, intel produced a uPD765-compatible FDC which they called 82077. Maybe
you have more luck finding that.
regards,
Michael
--
Michael Engel (en...@numerik.math.uni-siegen.de)
Microsoft is not the Borg collective. The Borg collective has got proper
networking.
Robert L. Doerr
> I'm looking for some spec sheets for a floppy disk controller chip in a DIP
> package. I know this is a bit vague but I am putting together a Z80 system from
> scratch and I have been looking for a FDC chip which I can use. I hope to get
> CP/M running on this thing. Most of the SMC chips are QPF chips which I can't
> work with. In searching for a controller I can work with I have found that many
> of the 40 pin DIP chips (Z0765A08, uPD765, 37C65CP) have been discontinued.
> Sombody must know of a manufacturer still supplying a DIP packaged chip.
>
> Thanks to everybody who helped with the memory mapper question. I'm still
> looking for spec sheets but at least I've got a start.
>
> Kurt McCullum
Check with B.G. Micro at:
They carry many of the older Western Digital disk controller chips as well as a
few other hard to find items. I bought a few from them in the past. Good luck
on your system.
Regards,
Robert
--
------------------------------------------------------------
Robert L. Doerr (MCNE, MCP, A+)
26308 Cubberness
St. Clair Shores, MI 48081
Tel: (810) 777-1313
e-mail: rdo...@home.com
WEB Site: http://www.robotswanted.com
"Keeping Personal Robots alive!"
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Ken Farmer
KDMcCullum wrote in message
<199809022013...@ladder03.news.aol.com>...
>I'm looking for some spec sheets for a floppy disk controller chip in a DIP
>package. I know this is a bit vague but I am putting together a Z80 system
from
I use the WD1771 which you can get from bgmicro.com. It is an old chip but
is easy to build around and program. It is a 40 pin dip. I have the set of
spec sheets which are sufficient to build and program from that I can send
you if you want. By coincidence I am currently building a 1771 FDC for an
S-100 8085 and a pair of Schugart 801 floppies.
kenfarmer47 at hotmail.com
Ken Farmer
Allison
>Sombody must know of a manufacturer still supplying a DIP packaged chip.
Check JDR or JAMCO, they are on the web. Also SMC supplies some
superintegration chips with a 765 core.
As to choices there are two 765 core or 179x core. Due to PCs the 765
core devices (765, 926x, 37c65, 92c665...) are dominent. The 179x
versions are getting scarce and very hard to find.
>Thanks to everybody who helped with the memory mapper question. I'm still
>looking for spec sheets but at least I've got a start.
Other than the 74*612 (*=ls or c) there are no mappers of any value
available. Check out the TCJ (I think it's WWW.PSYBER.COM/~TCJ) web
page there is an article there written by Tim Olmstead that describes
interfacing DRAM and Memory management. This is a very well written
article and you can lift the circuit from there to build a 1mb//4kpage
mapper that is real simple to put on a z80.
Having built several system using memory management on z80 and 8085
I can suggest two approaches. One is outlined in Tim's article, the
other is fairly simple and allows mapping the physical ram as two 32k
pages anywhere in a 16mb space. The unfortunate part is that in the
8085/z80 world memory management has never evolved a standard.
Though the z180 os clearly one possible standard that can be
duplicated as it's not that complex (code may still not be portable
as z180 as a few extra instructions for addressing internal ports).
Allison
Real address is: Allisonp @ world DOT std DOT com
++++BULK Email severely not wanted+++
Allison
>I use the WD1771 which you can get from bgmicro.com. It is an old chip but
The 1771 is single density and the later 1793 is the single/double
density version. The later is no harder to use, far more flexible and
just as easy to find.
>S-100 8085 and a pair of Schugart 801 floppies.
I happen to like the 8085 and use it alot for simple designs and
controllers. BUT: It locks you out of a significant portion of the
CP/M software written for z80. This is important as the 8080/8085
was relatively short lived in the cpm world and most of the major
packages were written to exploit the z80 to some degree.
timo...@cyberramp.net
>They carry many of the older Western Digital disk controller chips as well as a
>few other hard to find items. I bought a few from them in the past. Good luck
>on your system.
If he still has any left, look at the WD2793. It is a very easy chip
to work with, and it is s/w compatible with the older WD1793. The
WD2793 has an extreme advantage of having a built-in data seperator,
which saves you lots of hassle on your bd. I don't have any
programming info for it, but I do have schematics for an S100
controller bd that I did with it years ago. If you decide to use the
WD2793, I'll send you the schematics for my old bd.
Tim Olmstead
email : timo...@cyberramp.net
Visit the unofficial CP/M web site.
MAIN SITE AT : http://cdl.uta.edu/cpm
MIRROR AT : http://www.mathcs.emory.edu/~cfs/cpm
EUROPEAN MIRROR AT : http://cws86.kyamk.fi/mirrors/cpm/
Robert Hansen
I have a 1986 Western Digital Data book on hand, and would be glad to answer
any specific question that I can. I'm not an engineer, but I have worked with this
stuff quite a bit. (Actually I was a Customer engineer for Univac and Control Data
Corp)
Bob Hansen
rlha...@zianet.com
Frank Zsitvay
>
> Having built several system using memory management on z80 and 8085
> I can suggest two approaches. One is outlined in Tim's article, the
> other is fairly simple and allows mapping the physical ram as two 32k
> pages anywhere in a 16mb space. The unfortunate part is that in the
> 8085/z80 world memory management has never evolved a standard.
> Though the z180 os clearly one possible standard that can be
> duplicated as it's not that complex (code may still not be portable
> as z180 as a few extra instructions for addressing internal ports).
Given the proliferation of high speed static RAMs (>20 ns.) one could
also be used as a memory management unit.
This would work well in multitasking systems, since there would be
enough space to provide multiple memory configurations, one for each
task.
-Frank
Peter Heitzer
ATARI ST. The later is described in the "Atari ST Profibuch" for example.
--
Dipl.-Inform. Peter Heitzer, phone +49 941 943 4850, fax +49 941 943 4857
mail Peter....@rz.uni-regensburg.de
Allison
>> I can suggest two approaches. One is outlined in Tim's article, the
> Given the proliferation of high speed static RAMs (>20 ns.) one could
>also be used as a memory management unit.
Read the article off the TCJ web site. While it's titled DRAM
interfacing it describes using fast rams for MMU as you suggested.
No the system I built used several 74189 (4x16 ttl ram and fast) which
were common and cheap back 1981 to make a 4k paged mmu. no majik.
> This would work well in multitasking systems, since there would be
>enough space to provide multiple memory configurations, one for each
>task.
Yep, been there done that. It's a worthy effort still.
J.P.M. Bus
difference being the inverted data ?!? )
I should even have on around somewhere. The controller is half built
and will (one day) be finished and used in an old P2000T.
If you really need the data I can check for you.
Regards,
Hans Bus
timo...@cyberramp.net wrote:
--snip--
> If he still has any left, look at the WD2793. It is a very easy chip
> to work with, and it is s/w compatible with the older WD1793. The
--snip--
Walter Peterson
sells used Chips.
I have checked and JDR has Intel 8272 Floppy controllers which if memory serves is
a drop in replacement for the uPD765. Cost $.99
KDMcCullum wrote:
> I'm looking for some spec sheets for a floppy disk controller chip in a DIP
> package. I know this is a bit vague but I am putting together a Z80 system from
> scratch and I have been looking for a FDC chip which I can use. I hope to get
> CP/M running on this thing. Most of the SMC chips are QPF chips which I can't
> work with. In searching for a controller I can work with I have found that many
> of the 40 pin DIP chips (Z0765A08, uPD765, 37C65CP) have been discontinued.
> Sombody must know of a manufacturer still supplying a DIP packaged chip.
>
> Thanks to everybody who helped with the memory mapper question. I'm still
> looking for spec sheets but at least I've got a start.
>
> Kurt McCullum
Axel Berger
*Allison* wrote on Thu, 98-09-03 11:54 in comp.os.cpm:
A>The 1771 is single density and the later 1793 is the single/double
A>density version.
Is that 2793 or a chip I have not yet heard of? Is it really still made?
Danke
Axel
timo...@cyberramp.net
>-A3479@K2
The WD1793 is an older chip. It requires a seperate data seperator
ckt, which can sometimes be kindof finiky. The WD2793 has the data
seperator on-chip. and (IMHO) is easier to prototype with. It is s/w
compartible with the 1793.