Modified ST hassles

[ralcool]

3 HD boards are built tonight. And all tested working on a new patch harness in my ST.



My daughter won't let me make anymore just now.

Here they are...



Just a final trim on the linishing belt to pretty them up....

cheers.....

ps 1024Mak, I couldn't possibly attach my version of the modded 1.4 until I've finshed testing it.... and so far something seems wrong... more news later.

[ralcool]

Found this on the DoIT_ST archives today... is this the Joska of this forum???

""
Today I successfully accelerated my Stacy to 10MHz I'm currently testing it, so far it looks very stable. This was a very simple modification:


1.
Remove the original 32MHz oscillator and replace it with a 40MHz oscillator.

2.
Cut pin 3 and 4 on the two ACIAs (6350) and feed these pins with a 500KHz clock.

3.
Cut pin 18 on the floppy controller (1772-0x-0x) and feed it with a 8Mhz clock.

The 500KHz and 8MHz clocks can be generated by using the original 32MHz oscillator and a 74HC4024 (ripple counter).


This works very well on my Stacy, and everything is 25% faster. The Stacy's LCD controller works fine at this frequencey, but the shifter doesn't generate an image which works with TV's or my SM124 anymore. It does work with a SVGA, but the image is squashed.


It's also possible that I have to feed the YM with a 2MHz clock, I haven't tested this yet but the 74HC4024 generates 2MHz as well so this is not a problem.


I have a few more things to try out (e.g. I haven't tested the printer and modem ports yet, I have a 48MHz oscillator I'd like to try, will the ADSpeed16 work at 10/20MHz, will Mario's IDE interface work etc.), when this is done I'll upload a more detailed description to my homepage.



Jo Even Skarstein
http://home.nvg.org/ joska/

....""

I was thinking about replacing the 32mhz crystal in my ST with a 40mhz.... I have one spare on an old PC graphics card. Just to see what would happen.

Now I know what to do to make it work. Thanks Joska!

Maybe I can have the 10/20mhz instead from my overclock board. ('ve even contemplated installing the 16mhz cpu, and running 32mhz into the overclock board....... 16mhz into an 8mhz chip works reasonably well so far... Tempting eh?! Then it could be 8/32... or even 10/40mhz overclock!

[wongck]

Jo Even Skarstein
http://home.nvg.org/ joska/

Hey he frequent this forum. So just PM him @ joska

[DarkLord]

I know for sure Jo Even used to have a STacy, we have talked about mine from
time to time. So I'm betting it is the one and same...

[ralcool]

Finally, some nice news to report.

The recently built 'Tom K' mouse adapter finally recieved its new 16F84 chip. (Programmed on the finally recieved TOP2007 programmer)

I chose to omit the crystal oscillator from the design- but did allow for it, and instead fed it with 4mhz from the nearby MFP chip pin 35. (Generated from the MMU)

It works brilliantly. Using a nice Logitech 2 button ball mouse for now.

No more clunky clicking on the old Atari mouse.

Perhaps those guys who want to build an Atari/Amiga compatible 'new' mouse should consider a SMD version of the 16F84, and use this circuit inside.??! There is bugger all components required.

Computer porn.....


The circuit board needs a bit of a trim to reduce the excess pcb material, and still have to drill a new hole on the ST to mount the PS2 socket.... but the tests are complete. She works!

[Shredder11]

Simple and so elegant, very nice! I already have a PeST interface from the lovely Aly and would like another one, but I do not want to hassle her at the moment as she is busy with work; so yes...I do not want to be a PeST to her...

Her PeST though is probably the best PS/2 interface out there, because it is so tiny and she took a while writing the software (or her partner did) to put on the chip. I guess it took them a while to do due to the tiny amount of space for the code on the chip.

[wongck]

Yeap. I think this type of solutions are better because you do not replace the keyboard... with a PC keyboard like Eiffel does.
Also you can change the mouse as it is accessible rather than it being *inside* the mouse.

[ralcool]

You wouldn't believe this......

My video shifter chip failed last night. Was running the ST for a couple hours, playing some kids games with the daughter, then later some other stuff for me- the mouse tests and decided to run gembench for the hell of it while a bit bored.

Suddenly during the test the screen goes black. Power off, Power up... Nothing.

So, I checked all the connections to everything.... chip sockets etc.. but nothings been touched for a while really.

I have been using colour mode lately for the games, flicking the colour/mono switch on my little box- while the ST is powered.. naughty I know- but usually does a resets when switched- conveniently.

So now a dead ST... power up.. a brief flicker, and the ST actually boots IDE flickering away, LAscan BOOT sound- everything, but no picture.

Hmmm. Test voltage on the Mono detect pin of the shifter... always 0v.. strange. I notice in the schematic the mono pin on the shifter is pulled to ground by a resister, and goes to the 'base' of a small transister before going to the socket.

OK, Try a spare shifter chip...... I see about 2.5v in mono mode, and 0v in colour, and the ST has a picture again. phew. Swap back,..gone. Ok chip buggered. Plus the screen darkens when the meter touches the pin.... careful....

Maybe it NOT wise to change resolution via the switch while powered on.

We're fixed... but I've no more spare shifters if this one fails me!

[1024MAK]

I used to use a multi-sync monitor (i've still got it, but the picture has lost focus and it takes a while after turning on before the soft focus picture is just about usable ).
Anyway, when I did use it, I made up a box with a 13 way DIN plug with many wires (the video signals using mini 75 ohm screened cable) to it. Mounted in/on the box was a switch to change between mono and colour modes. The output signals were sent to a 9 way D connector, which is where the cable to the monitor was plugged in.
I mainly use medium res. but I did often switch to / or from mono just by using the switch (which was connected to the mono detect pin) while powered up.
Now this ST is the circa 1988 one that I have. It's still working okay to this day (used it yesterday in fact) .
So I don't think this is the primary cause of your shifter dying.
IIRC the only reason the ST performs a reset is because that's the way that Atari programmed the TOS. Some programmes and applications can change resolution on the fly without having to restart / reset the machine.
Still, at least you had a spare shifter

[1024MAK]

My video shifter chip failed last night.
~~~Snip~~~
Hmmm. Test voltage on the Mono detect pin of the shifter... always 0v.. strange. I notice in the schematic the mono pin on the shifter is pulled to ground by a resister, and goes to the 'base' of a small transister before going to the socket.

OK, Try a spare shifter chip...... I see about 2.5v in mono mode, and 0v in colour, and the ST has a picture again. phew. Swap back,..gone. Ok chip buggered. Plus the screen darkens when the meter touches the pin.... careful....

Err, are you on about the monochrome video output from the shifter (U49 pin 30) to pin 11 of the Monitor 13 way DIN socket via transister Q6, or are you on about the Monochrome Detect input on pin 4 of the Monitor 13 way DIN socket (this goes to pin 29 of U43, the 68901)?
Or are you confused and tired (I know i'm tired )
If your probing the monochrome video output, I would indeed expect a change of brightness on screen
Night, night time to generate some ZZZZZ's

[ralcool]

Erm, yeah... You right.. I am tired, and was looking at things wrong...

The chip is definately dead, and its maybe not suprising it failed during a graphics test!

Why... well, who knows. Old age.

[ralcool]

For info, I've bought some NEW Sony MPF920 FDD drives off ebay. (Including 2 black ones for STacy use!)

So... My HD FDD kits will INCLUDE a HD FDD drive, tested and working for HD mode.

There are currently 3 mods available, and soon with Sony drives corrected for ST use. (And enough parts to build another 5 mods) They will be modded for DS0 and HD detect...

This is as close to plug and play as I can build. Only 8 wires to solder, and the drives will be tested and ready to go! (You will have to slightly cut the ST case to fit them....sorry!)

If you want a modified TOS 1.4 Lo-0 chip, let me know. ( You can then BOOT from 1.44Mb disk without a 6ms step driver!.. but I can only do 6chip type TOS- Atari 2 chip style old roms are impossible to find)

Obviously the price will increase slightly to cover the drive cost..... but $A60 postage included, is a small price to pay for the complete tested package.

Whose in?

ps, Darklord- Your Stacy version will be completed by the end of the week.... I had to modify my PCB design for 'low profile' use. Socket-Less chip mounting, and resisters mounted flat to the pcb.
Do you want a ready to go black fdd drive?

Cheers folks!

[DarkLord]

You betcha!

[zackworld]

Ralcool.

Fantastic work you're doing
I've emailed you about an HD kit.
I guess I can't PM because I'm new

[ralcool]

Thy will be done. I saw the black ones for sale, and thought of you! The STacy has a normal looking drive face plate unlike the ST..

Saves the dramas of finding and possibly modding a suitable drive. (Like poor Spiny!)

Install and use. Can't get any easier.

For the older Ataris.. you have to trim the case around the button area at the minimum.

IMG_1539s.jpg

[wongck]

For my STFM using a replacement SONY floppy drive; I just need to break off the thinner part of the trapezoid hole, making enough room for the eject button.

[ralcool]

Ralcool.

Fantastic work you're doing
I've emailed you about an HD kit.
I guess I can't PM because I'm new

Didn't recieve the email..?!..but no matter. There are 3 boards sitting here waiting for someone that wants it.

I will have the new HD Sony drives sometime this week. All modded and ready to go after some brief work... Want one too?

When you can, PM me your address, And I'll add you to the list.

You can find me otherwise at sean.tremeer@gmail.com

PS, Darklord.. Your low profile HD board is finished & tested OK!...(only 7mm thick!) ...again just waiting on the drives to arrive... Maybe tomorrow... (Monday post..)
Sadly, the STacy runs a 2 chip 1.4 TOS.. and is difficult to offer you modified ROMs for 1.44Mb Booting...... But not impossible....just more challenging....

IMG_1547s.jpg

The 'FDD drive included' kits are nearly ready to go. (And a few more waiting to be built....if demand askes for it)

The 'tests' include, format both a 1.44Mb disk, and 720k on the 'internal' drive... then copy 700Kb from the DD external drive disk to HD internal... rinse and repeat variations....

Auto step rate version designs are around.. but have MUCH more logic chips, and calibration issues...... Maybe not. Just boot a simple 6ms driver, or run a slightly modified 1.4 6chip TOS, or even 2.06.
Easier. IMHO.

[DarkLord]

PS, Darklord.. Your low profile HD board is finished & tested OK!...(only 7mm thick!) ...again just waiting on the drives to arrive... Maybe tomorrow... (Monday post..)
Sadly, the STacy runs a 2 chip 1.4 TOS.. and is difficult to offer you modified ROMs for 1.44Mb Booting...... But not impossible....just more challenging....

Cool!

Right, space is a very big issue with the STacy in quite a few aspects. Accerator I've got is a special
make for the STacy (Tseries) - its half the height of the regular board.

No problem with the Auto booting, I can always load the step-rate software from the AUTO folder.
That's no biggie to me. I'd love to have TOS 2.06 chips in it, but I don't know how to do that, short
of surgery beyond my *very* meager soldering skills.

[ralcool]

I assume you tried softTOS2.06? Run from the Auto folder plus then you don't need the 6ms step driver, and score the new TOS! (Your STacy has a HDD?, it doesn't even reboot loading the new softTOS!)
Bonus,The 1.44Mb formatting option is enabled in the format menu... but it doesn't seem to work. Disks end up only 720k???!)

TOS_2_6.zip

Or, just a tiny 6ms setting program.

STEP6M.zip

Or the driver I gave the other guys.. it is a little fancier and includes a formatting accessory.

Elco_HD.zip

All will make HD mode work.


ps, Fcopy will make/format HD disks when configured correctly.

FCOPYPRO.rar

[zackworld]

Ralcool.
Didn't recieve the email..?!..but no matter. There are 3 boards sitting here waiting for someone that wants it.

I will have the new HD Sony drives sometime this week. All modded and ready to go after some brief work... Want one too?

When you can, PM me your address, And I'll add you to the list.
.

Thanks for that I'll email you direct for now and hopefully become a "Real Member" soon.

[DarkLord]

Not tried "Soft TOS 2.06"?

I tried PPera's SELTOS, which worked great from the desktop, but I never could get it
to work from the AUTO folder during bootup. I'm running HDDriver 8.15 and using an
UltraSatan.

Thanks for the links!

PS EDIT - doesn't the software loaded TOS's take up more memory than in ROM? Thx.

[ralcool]

You needed to use ramtos for Auto use.

Heres a pre-prepared slightly tweaked version of 2.06 by ppera that forces the display of the HD format option in the menu. (Given the older ST don't have the 'jumper pads to convince TOS to do so)
I asked him nicely, and heres what we got!!!!

AUTO_20.zip

All done, just unzip to 720k floppy and reboot.

You lose 256k of ram.....

[1024MAK]

Quote from ST Modifications underway

Hey 1024Mak.... Your MPF920 drive....

http://www.logicsays.com/atari/mpf920/
http://www.logicsays.com/atari/mpf920/images/image5.jpg

This site mentions a disk change detect/mod... are you finding any hassles regarding disk swap detection?

I have always pressed ESC when changing a disk to update folder.. and it always show the new disk contents..

My batch of 4 Sony drives will be here next week or so (2 white, 2 black) .. I'll test them all and modify them the same as you have.. DS0/HD.. and maybe disk change...

Might keep one for my ST.(But not modded for DS0, I modded my cable ) More available online from the sellers if I need more.

Interesting that mod is nothing like ppera using WP pin for similar result.
http://petari.000space.com/atari/flomodam.html

I have been meaning to investigate this for a while, but have not got around to it .

See also http://www.atari-forum.com/viewtopic.php?f=15&t=10873, http://www.atari-forum.com/viewtopic.php?f=15&t=10883, http://www.atari-forum.com/viewtopic.php?f=74&t=19148

At no point does Aly say why or how this works . As the Atari does not use pin 1, I can only presume that the drive does.

On part of a datasheet that I have for a Panasonic/Siemens drive (a second label {Siemens} is stuck over another label on the actual drive, the datasheet has the Panasonic name on it), model number JU-363, pin 1 is shown as an input "DISK CHANGE RESET". Alas, I do not have the whole document so I don't know much more . But on the datasheets for some other drives, pin 1 is not used for this function.

I have had an Atari STFM since 1988. This came with TOS 1.02, so yes I do know how very annoying it is when the machine does not want to discover that you have changed the disk
This machine came with a single sided drive, so it was not that long before I bought some surplus double sided drives .

As a result I used (and still use) two "work-arounds". First, for file operations etc I use NeoDesk (and press [Esc]) as TOS 1.02 is buggy in this area. When in an application, I use the other drive, or access a disk in the other drive, then swap back (but this does not always work! ).

On the machines that have TOS 1.04 or higher, I still tend to automatically press [Esc], but don't remember too many problems. Having said that, I also use NeoDesk on some of them as well...

I understand how the ppera mod. works, but have not tested it.

Have just finished 12 hour nights, so may drag myself to life later and do some testing...

PS: I hope this makes some (well a bit of) sense, bit tired, the old ALU is off-line [END OF LINE].....................................

[wongck]

As a result I used (and still use) two "work-arounds". First, for file operations etc I use NeoDesk (and press [Esc]) as TOS 1.02 is buggy in this area. When in an application, I use the other drive, or access a disk in the other drive, then swap back (but this does not always work! ).

On the machines that have TOS 1.04 or higher, I still tend to automatically press [Esc], but don't remember too many problems. Having said that, I also use NeoDesk on some of them as well...

.

yeah I remember those issue.
so I use a program like this to auto force a media change

[ralcool]

I've been trudging through the image for TOS 1.2 UK, I've found the location to patch it to 6ms...(position $2D9 to 00) . (I could do other languages on request btw)

(If you haven't been reading, this is to let the ST operate/boot a HD Floppy without a 6ms step 'driver' loaded from the AUTO folder from a HDD or 720k boot disk, with any kind of HD floppy kit)

So I can supply the single patched rom to fit in location Lo-0/U7/U67 for 6chip TOS1.2 set- just like 1.4......woot.

Alternately, I could supply a pair of roms wired like Kym suggested (nice idea btw) and you can upgrade you ST to TOS1.4 (also patched) using 27F/C 010 roms, and gain other benefits too!

http://www.atari-forum.com/viewtopic.php?f=15&t=16638

What do you make of that folks... only an extra wire to solder, I'll prepare the other pins for ya!

Only real catch being if your going from a six chip version 1.0 or 1.2, to this now two chip 1.4.. you won't have the 74LS11 that combines the rom select lines into two chip operation.
It can be added easily enough.to the ST U68 vacant spot for it .. but maybe a little too much for some..

If you already have a 2chip TOS, and a fair percentage of the older STs do.. your in LUCK!