MSTE SCSI/DMA and other internal upgrades

[vizfizz]

Now that I've resolved the HD floppy disk issue in my MSTE, I intend on upgrading it with some new capabilities. Whether its an HxC floppy emulator, Gotek, UltraSatan or ComosEX, I have a question regarding SCSI/DMA issues in the Mega STE.

 

The machine I have was previously used at an old factory..processing some manufacturing process I believe. Anyway... when the machine was sold to me, it looks like they pulled out the hard drive and the scsi controller card. The machine has seen better days, but I'm trying to make it like new again. According to Lotharek's website...here's what he has to say regarding upgrading a MSTE with an ultrasatan:

 

Note: When you remove the internal SCSI host adapter from Mega STE, the data bits (D0 - D7) on left of the internal ACSI connector will not be connected to the data bits on the right and thus the external DMA connector on MegaSTE will be unusable. A simple help might be just connecting those data bits with wires (and it might work), but the SCSI host adapter uses a 74HCT245 bus driver to connect those data lines together. This bus driver could be added to the PCB convertor but it requires some additional logic to merge CS and ACK signals to the 'G' signal of 74HCT245...

 

So my question is: If I no longer have a scsi host adapter that acts as a bridge to the external DMA, how will this limit the devices I can choose from to upgrade my MSTE? Will any of the hard drive replacements even work? Will I be limited to floppy drive emulators only on this machine?

 

[anzac]

i hope i can help you regarding using your DMA port as i hope you might be able to help me one day upgrade my MegaSTe to an HD floppy...

 

according to this thread:

 

http://atariage.com/forums/topic/181171-understanding-the-mega-ste/

 

and this post:

 

"That's not true (for change :-) ) . In case that no SCSI card, there should be bridge, what connects DMA with external ACSI port. If there is no such, you can place there 15 jumpers - and it will work - tested. If jumpers are problem, can solve in other way. Point is in connecting all neightbour pins on 2 connectors. "

 

-- credit to ParanoidLittleMan

 

 

it appears you have a simple solution...

 

best regards

[vizfizz]

Well that's good news. Thank you.

 

ParanoidLittleMan is quite helpful in his advice. He's been very helpful with my floppy drive situation.

 

If you have any questions regarding the HD floppy drive I'll be happy to help the best I can. I learned a lot.

[ParanoidLittleMan]

Here may see what you need in case of missing internal ACSI-SCSI adapter:

http://atari.8bitchip.info/MegaSTEACSI.html

First pic - 8 ordinary jumpers. There is no real need for bus driver. Which is not present btw. in most Ataris.

I would not go on some HW floppy emulator until floppy port is not fully functional - so works in DD mode too well.

UltraSatan is very popular and not expensive. Now we have plenty on SW fixed for mass storage. With CosmosEx can do many more, but there may be even more problems - I'm not sure that it can work as floppy emulator in High Density mode.

[Android8675]

With CosmosEx can do many more, but there may be even more problems - I'm not sure that it can work as floppy emulator in High Density mode.

 

I suspect CE won't do HD floppy discs. It mounts up to 3 disk images to the drive which you can switch between by pressing a button on the CE. I've never tried to do a HD Floppy (because my STe isn't modded for HD), but on the other hand the CE does work with the Falcon, doesn't that have HD discs? Either way the software can be patched, if the feature isn't there now it could possibly be added later.

 

You could also mount the CE as your B: drive in an external case and keep your HD floppy mounted internally. The STf has a mod for switching the A and B drives as well, I suspect the STe could receive a similar modification.

[vizfizz]

Very good points on both counts. I don't mind keeping the A drive a floppy in the MegaSTE if I can install a B drive floppy emulator somehow. How would that be possible? Or is my DD disk drive problems as drive A going to be a problem?

 

Since the Falcon and the MSTE are going to be my primary two workstations on this project I'm planning....I need an effective way to share files and information between the two. Plus I'm going to use an emulator to render and ray trace files with. If I can't network the machines together easily then transferring files via sd or usb seems the best choice.

[ParanoidLittleMan]

Problem is that your FDC is "tied" to 16MHz clock - or in other words in HD mode. So, it will work only with HD floppies and drives (or HW emulator capable to work in HD mode) on A and on B, until you fix error.

Considering data exchange: SD card would be relative simple solution. Then you need UltraSatan for MSTE, and 44pin IDE-SD adapter for Falcon, + Driver SW, of course. All it can be accessed on PC or MAC via USB card reader. Best if cards are partitioned TOS/DOS compatible.

[Android8675]

Very good points on both counts. I don't mind keeping the A drive a floppy in the MegaSTE if I can install a B drive floppy emulator somehow. How would that be possible? Or is my DD disk drive problems as drive A going to be a problem?

 

Since the Falcon and the MSTE are going to be my primary two workstations on this project I'm planning....I need an effective way to share files and information between the two. Plus I'm going to use an emulator to render and ray trace files with. If I can't network the machines together easily then transferring files via sd or usb seems the best choice.

 

You can mount the CE as your B drive, then mod your ST with a switch that swaps the A and B drive (you have to solder to your sound chip, you can google the mod online). I've never tried it, but it's on my list of things to experiment with.

 

Off the top of my head, if you had a CE in each of your STs you could use a network share folder on a connected PC to move files from one to the other, very easily. Save file to network drive on STe, load it onto your Falcon from the same drive.