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TRS-80 Hard Drive emulator demo and comparison with regular Tandy hard drive

Thanks for the video.

Good to see things like this for the TRS-80 series developed, and being available to the community. I intend to get one for my Model 4.

Tez
 
Lurker out of the dark: 118 views and one response? Shame on this community! :(

Hell yes I want one! Put me down for #2 after Tezza.

Should I pm you my PayPal password? :D

Mike
 
That's pretty neat, and I certainly might be interested in one or two, possibly in the "PIC and GALs included" kit form.

Out of curiosity: I've never owned a TRS-80 hard drive before, but I've heard the 4P can boot from one without a floppy. Any chance that might be supported by this hardware at some point, or is it not "register compatible" enough with the original to manage it? (Not a big deal if not, of course.)
 
That one in my video is the 8x300 controller from the old 26-1130 black 5 meg hard drives and early 26-4155W white 15meg hard drives (labelled Radio Shack), and although complex, its easy to understand and is basically very reliable.... the MFM hard drive will give out years before the HDC will.

Marmotking, any word on making it self boot on the 4P?

Ian.
 
I can answer that...
If it responds to the same addresses as a normal tandy controller, it will definitely work on a 4p.

Hale, I have an IDE adapter at those addresses, booting my 4p! I modified the boot code a touch (error flagging, delays, etc), but as I said...
:D

(I may be talking out my FIFO, since I cant watch the vid yet... no sound. :( )

EDIT:
After watching the vid, I stand by what I said... in fact, I think I want one too... to get rid of the 'mechanicals' if nothing else!
I would be using CP/M on it, and it can only handle 4x8Mb drive(s), so I could use the smallest SD I have (128mb) and still have 'spare' room!

The only problem I can see (for myself) is finding a 'compatible' partitioning scheme to use... or force the issue myself, as I did for the IDE.

quite exciting, this is! :D
 
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Hi guys, the prices are up on my web site:

http://ianmav.customer.netspace.net.au/trs80/emulator

and for those who wanted to know, here are some details of the Emulator team:

The Emulator team is as follows:

Fred Vecoven: concepts, engineer, protoypes, PCB design, firmware
web site: http://www.vecoven.com/
from: Belgium

Andrew Quinn: beta-tester, software developer (VHutil)
web site: http://www.quicktrip.co.nz/jaqblog/home/82-trs80m44
from: Auckland, New Zealand

David Cooper: beta-tester, other sytem adaptions
web site: www.trs-80.us
from: Seattle, Washington

Ian Mavric (me): beta-tester, assembly, marketing, videos
web site: http://ianmav.customer.netspace.net.au/trs80/
youtube: RE1974
from: Melbourne, Australia
 
From what Ive been reading on your page and the others, it seems this design MIGHT NOT BE compatible with CP/M, as it uses built-in accessibility to FatFS....

Did I read this wrong?

So :(
 
Leeb, I'd confer directly with Fred or Andrew, but the image file on the SD card is generated from the XTRS emulator. So in theory if XTRS can be used with CP/M then there is a good chance it will work with the FreHD drive.
 
So where does one obtain the source code if they want to build this onto a proto-board? For the GAL and PIC. I have a PIC programmer but not one for a GAL.
 
TRS-Ian said:
Leeb, I'd confer directly with Fred or Andrew, but the image file on the SD card is generated from the XTRS emulator. So in theory if XTRS can be used with CP/M then there is a good chance it will work with the FreHD drive.
Click to expand...

So... the emulator reads/writes to a FILE contained on a FAT filesystem on the SD?

The big question would be...
Does it respond with complete compatibility as a RAW HD... one that the CP/M (specifically Montezuma) would be able to configure with the software they provided?

*** AND BOOT FROM ? ***

IF that is true, then you will be sending me the build-it-urself kit sometime soon! :p

EDIT:
Will have to wait for contact w/ Fred since Im at work... :D
 
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Hi.

This is Fred, the designer of this emulator. To answer your questions : the emulator simulates the WD1010 interface to a Z80. The SD card is used obviously for storage, but not in raw mode. So you can have multiple hard drive images on the SD card. Currently, the emulator mounts up to 2 files (RSHARD/DCT supports only 2 files), but a simple re-compile can make it support 4 files, like a real WD1010. To the computer, the file appears as a real hard drive...

This has a little overhead, which is compensated by the ease of use. You can prepare your hard drive image on an emulator (I did everything with 'xtrs', from Tim Mann), copy that file to the SD card, and use it on the real machine. It is extremely convenient.

Regarding CPM, I haven't tried. But Andrew (a friend from NewZealand, beta-testing and developing utilities for the emulator) or I would be happy to test a CPM image. Prepare everything on 'xtrs', send us the file "hard4-0" and instructions, and we can test in a few minutes...

Your last question is "boot from...". If you can boot CPM from a real hard drive (on 4P ?), then it will probably work the same on the emulator. If not, too bad. I am considering starting an effort to hack the ROM to allow to boot LSDOS from the emulator, but that effort hasn't started yet (and I am getting very busy @work and with another project... that's also the reason why I decided to put all this as open-source, so people can modify/enhance and distribute..)

Cheers

-Fred
 
I forgot to add that the source code, PCB files, GAL equations will all be put on my website (which is down at the moment... I logged a ticket 12 hours ago).
 
veco said:
Hi.

This is Fred, the designer of this emulator. To answer your questions : the emulator simulates the WD1010 interface to a Z80. The SD card is used obviously for storage, but not in raw mode. So you can have multiple hard drive images on the SD card. Currently, the emulator mounts up to 2 files (RSHARD/DCT supports only 2 files), but a simple re-compile can make it support 4 files, like a real WD1010. To the computer, the file appears as a real hard drive...

This has a little overhead, which is compensated by the ease of use. You can prepare your hard drive image on an emulator (I did everything with 'xtrs', from Tim Mann), copy that file to the SD card, and use it on the real machine. It is extremely convenient.

Regarding CPM, I haven't tried. But Andrew (a friend from NewZealand, beta-testing and developing utilities for the emulator) or I would be happy to test a CPM image. Prepare everything on 'xtrs', send us the file "hard4-0" and instructions, and we can test in a few minutes...

Your last question is "boot from...". If you can boot CPM from a real hard drive (on 4P ?), then it will probably work the same on the emulator. If not, too bad. I am considering starting an effort to hack the ROM to allow to boot LSDOS from the emulator, but that effort hasn't started yet (and I am getting very busy @work and with another project... that's also the reason why I decided to put all this as open-source, so people can modify/enhance and distribute..)

Cheers

-Fred
Click to expand...

Yes... the 4P HAS the ability to boot from a properly configured hard drive... which is why the use of the '2' for a floppy boot while a drive is connected (It should be able to boot a properly configured LDOS 'drive' as well)...
I LIKE the idea of the file-based 'drive' although it might not be compatible with the 4p emulator I use... a minor inconvenience in the grand scheme.

THANK YOU for your prompt (early morning?) response!! I am excited about the possibility of putting a card slot on the front of my Model 4P! :p
:D

EDIT:
IIRC, I once saved off the 4p ROM... if I can find it, Id be happy to email it to you if you wish.
 
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I am in a business trip at the moment, in California, so that explains the time :) I am interested in the 4P rom, at least to give it a try on xtrs, and see how it goes with it.

Just curious, which 4P emulator do you use ? (the hard drive file format is the "reed" one (from Matthew Reed), which is, I believe, common across emulators now)

-Fred
 
I took a peek at the xtrs page and realized it is Keil's emulator I use... which would not be incompatible... supposedly.
His is configured for 4 drives (files) which could be a single drive partitioned...
It is able to use Montezuma's supplied drive formatters/configurators to enable a bootable image to generate the actual 'drive file'...
I SHOULD also be able to pull my working CP/M drive (1Px4L) and mirror it to a file.

I will attempt to track down that rom...

... from what I can see your site is running fine!
 
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