English Amiga Board


Go Back   English Amiga Board > Main > Amiga scene

 
 
Thread Tools
Old 09 September 2014, 22:50   #21
mark_k
Registered User
 
Join Date: Aug 2004
Location:
Posts: 2,703
Quote:
Originally Posted by alexh View Post
I am sure you've considered connecting your hard disk drives directly to your PC? Back in the day I had a PCI SCSI Ultra Wide card for my Windows PC with a super long data cable, didn't even take the hard drive out of my A3000, just swapped SCSI data cables.
I think it is/was possible in some circumstances to have two computers on the same SCSI bus. You need to change the SCSI ID of one of the controllers so they don't clash, and of course be careful not to access the same drive/partition from both computers at once. And also set one or both controllers not to reset the bus at power-on or reset. (So all in all, cool if you can get it to work, but getting it to work might be tricky.)
Quote:
Originally Posted by alexh View Post
I also had an 8-wire PC2Amiga parallel cable and SW on the PC and the Amiga. USB parallel ports are very cheap if a good transfer rate can be achieved? No need for external power supply. Software already available with source code.
You might be out of luck using a USB parallel cable for that, but I'd love to be proved wrong. (PC-side software might try to access native parallel port hardware directly, and/or the USB cable might not support all features of the parallel port.)
mark_k is online now  
AdSense AdSense  
Old 10 September 2014, 08:06   #22
JimDrew
Registered User

 
Join Date: Dec 2013
Location: Lake Havasu City, AZ
Posts: 496
Quote:
Originally Posted by ferix View Post
JimDrew, I like your idea, but I can't see how to 'hook' an alien filesystem to the operanting system... what's your idea?

I would love to see that
That's pretty simple really... an Amiga program that let's you select files to copy to/from the SD card.

Again the idea here is to be able to plug this device into any Amiga and dump it's files to a SD media, then remove that SD card and being cable to copy those files to a PC hard drive. I am not trying to copy files between Amigas.
JimDrew is offline  
Old 10 September 2014, 09:03   #23
fgh
Registered User
 
Join Date: Dec 2010
Location: Norway
Posts: 588
Sounds like a cool project!
Just making sure you are aware that winuae can use your amiga drives directly, or make images of them and use those.
fgh is offline  
Old 10 September 2014, 09:20   #24
Yulquen74
Registered User
 
Join Date: May 2013
Location: Kleppe / Norway
Posts: 162
Quote:
Originally Posted by JimDrew View Post
You can not FTP files to/from a machine that has no network access.
Thats why I suggested making a network adapter.

Quote:
Originally Posted by JimDrew View Post
I also need to support OS1.2 and later (my A1000 is still running OS1.2).
Now thats a showstopper.


Regarding power, can you not drain it from the video connector?
If you are using that port for your monitor, an Y-cable could me made to extract the 12V.
Yulquen74 is offline  
Old 10 September 2014, 18:05   #25
JimDrew
Registered User

 
Join Date: Dec 2013
Location: Lake Havasu City, AZ
Posts: 496
Quote:
Originally Posted by Yulquen74 View Post
Thats why I suggested making a network adapter.



Now thats a showstopper.


Regarding power, can you not drain it from the video connector?
If you are using that port for your monitor, an Y-cable could me made to extract the 12V.
You can't network two machines located miles apart when there is no network connection available.

There is power from the floppy port too. I was just trying to keep the device as simple as possible and DB23 connectors are a bit rare (although I still have hundreds of them from Supercard Ami, AMIA, and SYBIL productions).
JimDrew is offline  
Old 10 September 2014, 21:03   #26
Yulquen74
Registered User
 
Join Date: May 2013
Location: Kleppe / Norway
Posts: 162
Quote:
Originally Posted by JimDrew View Post
You can't network two machines located miles apart when there is no network connection available.
Sorry, I missed your second point in post #18 where you mention machines in different locations, I assumed you had a PC available where the
Amiga was, which is the usual scenario.
Yulquen74 is offline  
Old 11 September 2014, 04:41   #27
JimDrew
Registered User

 
Join Date: Dec 2013
Location: Lake Havasu City, AZ
Posts: 496
I would like to be able to walk over to an Amiga in one room, dump it's contents, drive home and then copy that data to my PC so I can use the data under WinUAE or Replay or one of my other Amigas!
JimDrew is offline  
Old 11 September 2014, 05:18   #28
ancalimon
Supernormal

ancalimon's Avatar
 
Join Date: Jul 2007
Location: Istanbul / Turkey
Age: 36
Posts: 1,229
Quote:
Originally Posted by mark_k View Post
I think it is/was possible in some circumstances to have two computers on the same SCSI bus. You need to change the SCSI ID of one of the controllers so they don't clash, and of course be careful not to access the same drive/partition from both computers at once. And also set one or both controllers not to reset the bus at power-on or reset. (So all in all, cool if you can get it to work, but getting it to work might be tricky.)
I would be very interested in doing this witchcraft

So this works by inserting one end of the cable to the PC?

How do you set computers to not to reset the bus at power-on or reset?
ancalimon is offline  
Old 11 September 2014, 14:22   #29
mark_k
Registered User
 
Join Date: Aug 2004
Location:
Posts: 2,703
Quote:
Originally Posted by ancalimon View Post
I would be very interested in doing this witchcraft

So this works by inserting one end of the cable to the PC?

How do you set computers to not to reset the bus at power-on or reset?
You have both computers on the SCSI bus, they don't have to be at the ends. Though if a SCSI card has hard-wired termination which can't be disabled (I think my GVP card is like that) it would need to be at the end.

Looking at pics of the A2091 and a couple of GVP controllers, they don't seem to have any way to select the controller's SCSI ID. You'd probably have more luck choosing a SCSI card for the PC that allows its ID to be changed. The PC card might have some utility that you run to change options; Adaptec cards use a program called SCSISelect. That can also be used to disable the card's SCSI bus reset.

The SCSI FAQ has a section about sharing the bus. Also it seems the Siamese System from HiQ Ltd. used a shared PC-Amiga SCSI bus.

It could/should be possible to have WinUAE running on the PC, booting from a local HDF but accessing the SCSI drive as a data drive. Copy lots of files to the SCSI drive then run DiskChange on the Amiga to make it recognise the updated drive contents. And similarly in reverse. You'd have to be very careful to always use DiskChange, otherwise the partition could become corrupted.

Last edited by mark_k; 11 September 2014 at 14:31.
mark_k is online now  
Old 11 September 2014, 19:51   #30
JimDrew
Registered User

 
Join Date: Dec 2013
Location: Lake Havasu City, AZ
Posts: 496
SCSI controllers default as ID 7, so you would need some way to change that.
JimDrew is offline  
Old 12 September 2014, 13:09   #31
alexh
Thalion Webshrine
alexh's Avatar
 
Join Date: Jan 2004
Location: Oxford
Posts: 11,943
For the A3000 it is saved in BattMem

http://aminet.net/package/util/wb/SetBatt-1.2

SetBatt ScsiHostId <0..7>
alexh is offline  
Old 12 September 2014, 15:32   #32
ferix
Registered User
ferix's Avatar
 
Join Date: Sep 2009
Location: Spain
Age: 40
Posts: 95
All PC SCSI controllers I've had had a way of changing its default ID (BIOS, jumpers, microswitches, etc.)...
But I think we're missing the point...

By other hand, JimDrew, if you're going to write an specific program for data transfer, why do you need to write a system driver?

Last edited by prowler; 12 September 2014 at 22:06. Reason: Back-to-back posts merged.
ferix is offline  
Old 12 September 2014, 17:24   #33
JimDrew
Registered User

 
Join Date: Dec 2013
Location: Lake Havasu City, AZ
Posts: 496
Because that is the proper thing to do. Making a device driver would allow anyone to then use standard device driver calls for read, write, get geometry, etc. I wrote a lot of device drivers, so I just need to add the parallel transfer code and a few device specific functions to one of them and that's it to get that done.

I am laying out a board this weekend and I will have boards by the end of next week to stuff and test. I will test it with a DOSDriver using CrossDOSFileSystem first to see what the speed is. If it's >150KBs then I won't need the transfer program. My concern is speed of the file system handler vs. an on-board FAT32 handler. I will have the option for either method, but I could get away with a much smaller PIC if I can ditch the file handler.

Last edited by JimDrew; 12 September 2014 at 17:32.
JimDrew is offline  
Old 12 September 2014, 21:38   #34
pandy71
Registered User
 
Join Date: Jun 2010
Location: PL
Posts: 1,546
Quote:
Originally Posted by JimDrew View Post
After thinking about the floppy port a bit more, that idea is completely out because you have to emulate a disk drive and although I can certainly do that (and will be with SuperCard Pro, much like the HxC does) the speed would be dramatically lower than I was thinking because you would need to use MFM encoding/decoding because you can't write all values (0-255) as MFM.
Nope - MFM is for magnetic storage but for non-magnetic storage you are quite free (i assume speed can be almost doubled when compared to FDD).
Side to this port lines can be used to increase speed (CIA is programmable and there is lot of lines to use in non standard way but still it can provide compatibility with FDD).
Using FDD port have one advantage - you can boot any Amiga without special driver (so first slow second with reuse CIA lines way faster) and power can be provided as required...
pandy71 is offline  
Old 13 September 2014, 01:05   #35
voyager
The show must go on.
voyager's Avatar
 
Join Date: Dec 2010
Location: Alkmaar Nederland
Posts: 237
Send a message via MSN to voyager
This maybe a stupid suggestion, but why not use a serial bluetooth connexion on the serial port? Or interface it to the printer port?
voyager is offline  
Old 13 September 2014, 01:07   #36
JimDrew
Registered User

 
Join Date: Dec 2013
Location: Lake Havasu City, AZ
Posts: 496
Quote:
Originally Posted by pandy71 View Post
Nope - MFM is for magnetic storage but for non-magnetic storage you are quite free (i assume speed can be almost doubled when compared to FDD).
That's not actually true. There are specific byte combinations that trigger certain things when dealing with MFM data and flux level data. Paula is by far more carefree than the WD177x series, but you still can't use every byte (0x00-0xFF) in the MFM data. I know a little bit about Paula and floppy drives... I created Supercard Ami, Supercard Ami II, SYBIL, and AMIA hardware devices for the Amiga to copy/image floppy disks. I make a product right now that also images/copies floppys:

http://www.cbmstuff.com/proddetail.php?prod=SCP

Besides giving you the ability to backup your software, this product creates flux-level images that can be used under WinUAE, FS-UAE, E-UAE, and FPGA Arcade Replay to give you an exact emulation of a real disk, just as real hardware (Paula) sees it.
JimDrew is offline  
Old 13 September 2014, 01:07   #37
JimDrew
Registered User

 
Join Date: Dec 2013
Location: Lake Havasu City, AZ
Posts: 496
Quote:
Originally Posted by voyager View Post
This maybe a stupid suggestion, but why not use a serial bluetooth connexion on the serial port? Or interface it to the printer port?
Serial would be too slow. The parallel port is the "printer port", and that is what I am using.
JimDrew is offline  
Old 13 September 2014, 02:03   #38
K.C.Lee
Registered User

 
Join Date: Jul 2014
Location: Ottawa/Canada
Posts: 49
May be something simple like bit-banging the SD from the parallel port with a level shifter to 3.3V. Not going to be fast as you are limited by the E clock cycles (< 200kB/s), but doable. You can probably whip up a device driver that make it look like a block level device.
-- Edit
Oops. Wrong units. bits.

"Arduino" SD breakout boards from China/Ebay that has on board level shifter already. Matter of hooking up the pins to the parallel port.

If you can move a hard drive from the Amiga to the PC, then there are ways of reading that off. For linux, it is easy. For windows, you can copy files on the hard drive/hard drive image file with this:

http://archives.aros-exec.org/share/...ad_afs_0.1.zip

Last edited by K.C.Lee; 13 September 2014 at 12:33.
K.C.Lee is offline  
Old 13 September 2014, 05:09   #39
JimDrew
Registered User

 
Join Date: Dec 2013
Location: Lake Havasu City, AZ
Posts: 496
That is exactly what Ferix is doing with his project. Bit-banging the SPI requires sending a dummy byte for every byte you receive. Add another byte for handshaking and now you have reduced the maximum speed considerably. There is also a LOT of setup to just send a command to the SD card for each block and that data would have to be sent over the parallel port too, killing speed.

By using just the parallel port (and it's auto strobe/ack features), I can send just a block number to fetch from the Amiga side and the PIC gets the data via DMA'ing the SPI port to internal RAM. Since the SPI bus is way faster than the parallel port the transfer back to the Amiga can occur as soon as the buffer starts getting filled. This reduces the overhead of having to wait for data to send (although the SPI is typically 20MHz for SD cards). When data is being sent to the card for storage, it can go into a dual "ping-pong" buffer that will DMA the data to the card while potentially another block is being sent to the other buffer. It only takes a 20 pin PIC really to do it. But I am using a 28 pin PIC and adding some other "things".
JimDrew is offline  
Old 13 September 2014, 10:57   #40
ferix
Registered User
ferix's Avatar
 
Join Date: Sep 2009
Location: Spain
Age: 40
Posts: 95
Well, I'm not actually "bit-banging", I'm just reading/writing bytes from/to the parallel port.

The real problem here is the damn slow CIA access, and the way it works.

My interface starts sending every byte it receives when you write to the port B of the CIA, sensing the STROBE pin (the CIA generates one cycle low pulse on STROBE for each byte written/read to/from the port).

But for reading a byte from the SPI, you first have to write something to it, usually a dummy byte (0xFF).
And that's not the only issue here... Every time you change from read to write or viceversa, you need to write 2 more bytes to the CIA (set port to in/out and change output control line).

So, a basic SPI transfer goes like this:
1) Assuming the CIA port B is in output mode, and the control line is set, you write your data to the port. 1 CIA access
2) Now you change the port B to input mode, and clear the control line (to tell the interface we're going to read from it). 2 CIA accesses
3) If you want to continue working, you should put back the CIA in output mode, and set again the control line. 2 CIA accesses

So you need 5 accesses to the (very) slow CIA, and taking in mind that CIAs are clocked at about 1 Mhz (in fact, even less), the typical access time is around 1 usec, thus you're actually spending 5 usecs on each SPI transfer...

And don't forget that there's no cache or pipelines on a plain 68000, so it's going to take even longer... (cpu has to fetch the opcodes from memory, execute them, move data from/to internal registers to/from memory, etc...).

I'm using some unrolling techniques to speed up some things, trying to minimize jumps and all those things that last forever in a 68000, getting close to a 2x performance boost over an unoptimized code.

All this means that the faster I can go in a bare A500 is around 25 Kbytes/sec (actually 27 Kbytes/sec), and close to 50 Kbytes/sec on a '060 A1200 machine (just 48,5 Kbytes/sec).

So, get your own conclusions...

Last edited by ferix; 13 September 2014 at 11:08.
ferix is offline  
AdSense AdSense  
 


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Similar Threads
Thread Thread Starter Forum Replies Last Post
PCMCIA CF card adapter, that I can buy online? theshinyknight support.Hardware 13 07 November 2013 08:52
CF Card or Adapter Problem spanner support.Hardware 12 30 July 2012 19:38
Transcend - Card adapter ( CF I ) - PC Card spannernick support.Hardware 6 09 May 2012 21:58
PCMCIA adapter with 256mb CF Card issue smeghead support.Hardware 6 01 July 2011 11:23
A4000D cf card adapter and cdrom heALer support.Hardware 39 23 January 2011 22:05

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +2. The time now is 00:03.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Page generated in 0.27646 seconds with 11 queries