Convert ST354 to DS/DD drive

[amiman99]

I posted this in different forum, but I got no responses....

 

Hi,

 

My drive finally gave out, would not format disks anymore, also the belt broke too. After replacing the belt with rubber band, it made it spin, but still no format anymore.

 

So I installed a DS/DD drive (HD too) Epson SMD-320 into it, it works fine in Single Side Mode, but it won't format in Double Side.

 

Can someone tell me what else I need to do for Atari ST recognize that I have Double Sided drive. I read some other forums that I need to only do the swap, but is not working like that. In the Atari pin outs I did see pin for "Side 0 Select", but on the floppy pin out there is no pin "Side 0 Select". Extra pins I found were: "Density Select" and "Disk Change/ Ready"

 

I have seen some one posting that they replaced the drive with double density and it worked, but it does not in may case.

 

By default the voltage at pin 32 "Side Select" is 4.7VDC, when I grounded the pin, I was able to format the other side.

 

Also the ribbon cable is too short and I can't do the twist, I need some ribbon extender, because the other side of the ribbon is soldered.

 

Thanx.

 

I got some parts to replace the original ribbon cable...here is the pic

[tjlazer]

I had a bad SF314 drive so I swapped in a Chinon FZ-357 HD drive and set it to DS0 and it works 100%... Try a different mech maybe? Should work out the box...

 

I also had a bad mech in a GTS-100 drive and dropped in an Epson SMD-340 and it also works 100%... Never heard of the SMD 320... Maybe it's not 100% compatible?

 

 

Haha look what I found:

http://www.update.uu.se/~ronny/ataridoubledrive.jpg

Edited September 20, 2009 by tjlazer

[Shredder11]

LOL! I think it maybe needs a few more cosmetic finishing touches, to make it easier on the eye though...

[amiman99]

I did not have solder sucker that time, so the wire did not go through, I'll fix it, I promise!

 

anyway, the drive works fine in single sided mode, I think it's the PCB blocking the side change signals. I will try to isolate it first to see what happens.

[papa_november]

The connector PCB still has some of the hardware used to run the old drive on it. The floppy drive should be connected straight through to the DIN-14 connector. You'll need to get rid of those extra chips and bypass them somehow.

[homerwan]

I posted this in different forum, but I got no responses....

 

Hi,

 

My drive finally gave out, would not format disks anymore, also the belt broke too. After replacing the belt with rubber band, it made it spin, but still no format anymore.

 

So I installed a DS/DD drive (HD too) Epson SMD-320 into it, it works fine in Single Side Mode, but it won't format in Double Side.

 

Can someone tell me what else I need to do for Atari ST recognize that I have Double Sided drive. I read some other forums that I need to only do the swap, but is not working like that. In the Atari pin outs I did see pin for "Side 0 Select", but on the floppy pin out there is no pin "Side 0 Select". Extra pins I found were: "Density Select" and "Disk Change/ Ready"

 

I have seen some one posting that they replaced the drive with double density and it worked, but it does not in may case.

 

By default the voltage at pin 32 "Side Select" is 4.7VDC, when I grounded the pin, I was able to format the other side.

 

Also the ribbon cable is too short and I can't do the twist, I need some ribbon extender, because the other side of the ribbon is soldered.

 

Thanx.

 

I got some parts to replace the original ribbon cable...here is the pic

Hi,i have the same problem with de floppy drive and it doesen´t work in double side, can you tell me how did you repair it? becouse i don´t understand very well the 32 pin grounded. how you did it? thanks a lot

[tjlazer]

Drive is incompatible, get another drive mech or mod the drive to work. Do a search as I dont know what needs to be done.

[AstFan]

My drive finally gave out, would not format disks anymore, also the belt broke too. After replacing the belt with rubber band, it made it spin, but still no format anymore.

So I installed a DS/DD drive (HD too) Epson SMD-320 into it, it works fine in Single Side Mode, but it won't format in Double Side.

Can someone tell me what else I need to do for Atari ST recognize that I have Double Sided drive. I read some other forums that I need to only do the swap, but is not working like that. In the Atari pin outs I did see pin for "Side 0 Select", but on the floppy pin out there is no pin "Side 0 Select". Extra pins I found were: "Density Select" and "Disk Change/ Ready"

I have seen some one posting that they replaced the drive with double density and it worked, but it does not in may case.

By default the voltage at pin 32 "Side Select" is 4.7VDC, when I grounded the pin, I was able to format the other side.

 

Drive is compatible - side select pin is standard, so not possible that it's the problem.

Likely, there is a failure in your PSG chip, what drives (unbuffered) side selection.

Btw. you should not ground those pins to GND, it may damaging PSG chip for instance.

And no need for do anything that Atari ST recognise DS drive.

So, you should replace PSG chip.

[homerwan]

My drive finally gave out, would not format disks anymore, also the belt broke too. After replacing the belt with rubber band, it made it spin, but still no format anymore.

So I installed a DS/DD drive (HD too) Epson SMD-320 into it, it works fine in Single Side Mode, but it won't format in Double Side.

Can someone tell me what else I need to do for Atari ST recognize that I have Double Sided drive. I read some other forums that I need to only do the swap, but is not working like that. In the Atari pin outs I did see pin for "Side 0 Select", but on the floppy pin out there is no pin "Side 0 Select". Extra pins I found were: "Density Select" and "Disk Change/ Ready"

I have seen some one posting that they replaced the drive with double density and it worked, but it does not in may case.

By default the voltage at pin 32 "Side Select" is 4.7VDC, when I grounded the pin, I was able to format the other side.

 

Drive is compatible - side select pin is standard, so not possible that it's the problem.

Likely, there is a failure in your PSG chip, what drives (unbuffered) side selection.

Btw. you should not ground those pins to GND, it may damaging PSG chip for instance.

And no need for do anything that Atari ST recognise DS drive.

So, you should replace PSG chip.

 

where is the psg chip, and what is that?

So the only way to make the games of 720k or 800k work is making a format of one side of those capacities and then what?

Sorry my bad english and sorry for bother you.

Thanks a lot guys and thanks for your quick responses.

i´ll be waitting for more

[AstFan]

 

where is the psg chip, and what is that?

So the only way to make the games of 720k or 800k work is making a format of one side of those capacities and then what?

Sorry my bad english and sorry for bother you.

Thanks a lot guys and thanks for your quick responses.

i´ll be waitting for more

 

PSG chip is Programmable Sound Generator. But it has 8-bit port too, what is used for some functions as drive select (A or B) and floppy side select.

You may look some ST schematics here: http://dev-docs.atariforge.org/

Bad thing is that those lines go directly to floppy connector, what makes them easy damageable - what happened to me many years ago, and I needed to replace PSG chip.

 

PSG chip has 40 pins, location varies by motherboard revision.

Formatting of DS floppies , so 720 or 800K goes like: formatting first track 0, side 0, then track 0 side 1, then step to track 1 and so on. This way requires less stepping.

[homerwan]

My drive finally gave out, would not format disks anymore, also the belt broke too. After replacing the belt with rubber band, it made it spin, but still no format anymore.

So I installed a DS/DD drive (HD too) Epson SMD-320 into it, it works fine in Single Side Mode, but it won't format in Double Side.

Can someone tell me what else I need to do for Atari ST recognize that I have Double Sided drive. I read some other forums that I need to only do the swap, but is not working like that. In the Atari pin outs I did see pin for "Side 0 Select", but on the floppy pin out there is no pin "Side 0 Select". Extra pins I found were: "Density Select" and "Disk Change/ Ready"

I have seen some one posting that they replaced the drive with double density and it worked, but it does not in may case.

By default the voltage at pin 32 "Side Select" is 4.7VDC, when I grounded the pin, I was able to format the other side.

 

Drive is compatible - side select pin is standard, so not possible that it's the problem.

Likely, there is a failure in your PSG chip, what drives (unbuffered) side selection.

Btw. you should not ground those pins to GND, it may damaging PSG chip for instance.

And no need for do anything that Atari ST recognise DS drive.

So, you should replace PSG chip.

so you say it´s compatible and the problem is that cursed chip?

the chip handled the two heads of the floppy drive?

where can i buy one of this and what model do i have to buy?

btw my atari is a 520 stm

thak´s to all for help me

Edited June 18, 2010 by homerwan

[tjlazer]

well it would be nice if you have a working drive to test on your 520 or use another machine on your drives...

[AstFan]

 

so you say it´s compatible and the problem is that cursed chip?

the chip handled the two heads of the floppy drive?

where can i buy one of this and what model do i have to buy?

btw my atari is a 520 stm

thak´s to all for help me

 

According to what you described here, 99% that PSG chip is broken. But it would be good that you check connector(s) - and if can measure that side (head) select line from PSG chip to floppy drive connector - with ohmmeter. If line (or connector) is broken, it is always high level on that pin (at floppy connector) due to pull-up resistor.

I don't know is that chip available still - pretty old thing. Chip is YM2149 .

[homerwan]

 

so you say it´s compatible and the problem is that cursed chip?

the chip handled the two heads of the floppy drive?

where can i buy one of this and what model do i have to buy?

btw my atari is a 520 stm

thak´s to all for help me

 

According to what you described here, 99% that PSG chip is broken. But it would be good that you check connector(s) - and if can measure that side (head) select line from PSG chip to floppy drive connector - with ohmmeter. If line (or connector) is broken, it is always high level on that pin (at floppy connector) due to pull-up resistor.

I don't know is that chip available still - pretty old thing. Chip is YM2149 .

Ok, im gonna test the pinouts the connectors and see what next.

do you think its possible to replace the chip with the AY-3-8910.

 

thaks again to all

[AstFan]

 

Ok, im gonna test the pinouts the connectors and see what next.

do you think its possible to replace the chip with the AY-3-8910.

 

Right - that chip is equivalent to YM2149.

[homerwan]

 

Ok, im gonna test the pinouts the connectors and see what next.

do you think its possible to replace the chip with the AY-3-8910.

 

Right - that chip is equivalent to YM2149.

 

I checked the pins and the results are....

in 200 omhs (pin 32 (floppy)---------pin 21 (YM2149) = 06.1 omhs)

in 200 omhs (pin 32 (floppy)---------pin 26 (YM2149) = 74.3 omhs)

 

Thanks for you patience

[AstFan]

 

I checked the pins and the results are....

in 200 omhs (pin 32 (floppy)---------pin 21 (YM2149) = 06.1 omhs)

in 200 omhs (pin 32 (floppy)---------pin 26 (YM2149) = 74.3 omhs)

 

Thanks for you patience

 

Yes, pin 21 is the side select one. 6 ohms is normal resistance, so connectors are OK.

You are welcome. And I'm refreshing little my Atari HW knowledge :-)

[homerwan]

 

I checked the pins and the results are....

in 200 omhs (pin 32 (floppy)---------pin 21 (YM2149) = 06.1 omhs)

in 200 omhs (pin 32 (floppy)---------pin 26 (YM2149) = 74.3 omhs)

 

Thanks for you patience

 

Yes, pin 21 is the side select one. 6 ohms is normal resistance, so connectors are OK.

You are welcome. And I'm refreshing little my Atari HW knowledge :-)

So, maybe the ym2149 is not working right, or the 1.44 drive is bad?

what do you think?

Ps: if i fix this, of course with the help of all of you, im goona be very happy.

[homerwan]

 

I checked the pins and the results are....

in 200 omhs (pin 32 (floppy)---------pin 21 (YM2149) = 06.1 omhs)

in 200 omhs (pin 32 (floppy)---------pin 26 (YM2149) = 74.3 omhs)

 

Thanks for you patience

 

Yes, pin 21 is the side select one. 6 ohms is normal resistance, so connectors are OK.

You are welcome. And I'm refreshing little my Atari HW knowledge :-)

 

Hi again, do you think those cables are correct?

or just with a plane one must work properly?

Im using an EPSON 300 Floppy drive with D0-D1 Jumper select.

What do you think?

Thanks again

[AstFan]

 

Hi again, do you think those cables are correct?

or just with a plane one must work properly?

Im using an EPSON 300 Floppy drive with D0-D1 Jumper select.

What do you think?

Thanks again

 

I don't see well how those cables are twisted. But rule for Atari floppy is: no any twisting on cable - so plane. Drive must be set as D0 .