• Please review our updated Terms and Rules here

Putr under dosemu?

8008guy

Veteran Member
Joined
Jun 25, 2014
Messages
584
Location
Salt Lake City, Utah
Does putr run under dosemu?

I'm trying to build a rt11 boot disk. Whenever I run a format, or mount the A drive putr hangs. It seems to run ok under dos, although I haven't got a mountable system disk yet. DOS tends to be a pain due to lack of networking... :(

len
 
I guess I need to resist the temptation to ask multiple questions in one message...

To simplify this...

Has anyone successfully ran putr in dosemu under linux. When I do so it hangs.
 
I haven't run putr (nor have any need for it), but it doesn't seem like it's the sort of program that would work under DOSEMU. Based on what it does I'd assume it expects to be able to directly twiddle the floppy drive controller and DOSEMU isn't set up to allow that.

Here's a short blurb about setting up Linux's native floppy driver to be able to format/dd an RX-50 floppy. Since it appears putr has the capability to work with disk images I suppose it's possible if you can replicate the native geometry of your target floppy type like this you could use a combination of putr and dd to work with floppies (by going through an intermediate imaging step) without booting to DOS. But that's totally just spitballing.
 
Thanks,

I have been using dd to move images around once I've created the boot disks with putr.

Are either SIMH or E11 capable of creating bootable images that I can dd to floppy and get to boot on a real PDP11? I'm using RX23 disks.

len


I haven't run putr (nor have any need for it), but it doesn't seem like it's the sort of program that would work under DOSEMU. Based on what it does I'd assume it expects to be able to directly twiddle the floppy drive controller and DOSEMU isn't set up to allow that.

Here's a short blurb about setting up Linux's native floppy driver to be able to format/dd an RX-50 floppy. Since it appears putr has the capability to work with disk images I suppose it's possible if you can replicate the native geometry of your target floppy type like this you could use a combination of putr and dd to work with floppies (by going through an intermediate imaging step) without booting to DOS. But that's totally just spitballing.
 
Thanks,

I have been using dd to move images around once I've created the boot disks with putr.

Are either SIMH or E11 capable of creating bootable images that I can dd to floppy and get to boot on a real PDP11? I'm using RX23 disks.

len

You should be able to do that. Do you have the RX23 drive (1.44 MB 3.5") cabled up to an M7555 RQDX3? I have never tried that combination myself, only RX33 drives (1.2 MB 5.25").
 
I hope to use a standard floppy on Malcolm Macleod's break out board. Boards show up tomorrow. If all goes well I will have one built to try over the weekend. I have the RX23 disk built and working from the hardware floppy running on both SIMH and E11. I patched SIMH to recognize RX23's. I'm keeping my fingers crossed.

http://www.avitech.com.au/pdp-11-03/rqdx-wiring.html



You should be able to do that. Do you have the RX23 drive (1.44 MB 3.5") cabled up to an M7555 RQDX3? I have never tried that combination myself, only RX33 drives (1.2 MB 5.25").
 
I hope to use a standard floppy on Malcolm Macleod's break out board. Boards show up tomorrow. If all goes well I will have one built to try over the weekend. I have the RX23 disk built and working from the hardware floppy running on both SIMH and E11. I patched SIMH to recognize RX23's. I'm keeping my fingers crossed.

http://www.avitech.com.au/pdp-11-03/rqdx-wiring.html

Hmm, now that I think about it, while a 3.5" drive might work fine cabled up to an M7555 RQDX3 an operating as an equivalent to an RX33 5.25" drive, there might be issues trying to exchange the floppy media between that system and a PC expecting normally formatted 3.5" floppy media.

What exactly does it mean to patch SIMH to recognize RX23's? If the 3.5" floppy media is formatted in the standard 1,440KB HD format I don't think that will really be compatible with the RQDX3 firmware.
 
Crawford and I analyzed the RQDX3 connected RX23 in an earlier thread (the one about the Gotek floppy emulator on RQDX3). Indeed it does operate equivalent to RX33, same number of data sectors per track. I don't think I tried to mount that floppy under PUTR, but I did look at it with IMGDSK.

Lou
 
Crawford and I analyzed the RQDX3 connected RX23 in an earlier thread (the one about the Gotek floppy emulator on RQDX3). Indeed it does operate equivalent to RX33, same number of data sectors per track. I don't think I tried to mount that floppy under PUTR, but I did look at it with IMGDSK.

Lou

So if you attach an RX23 to an RQDX3 and low level format an erased 3.5" HD floppy as through it were an RX33 drive and media using ZRQCH0, and then also attach the RX23 drive to a PC and low level format an erased 3.5" HD floppy there and compare the result of using ImageDisk to look at the two floppies, are the results the same except for sectors per track, 15 vs. 18, or does ImageDisk report different data rates as well?

Just because ImageDisk might be able to identify the RQDX3 low level floppy format in terms of sectors per track and data rate, if it not what is normal for a PC system would you be able to get Linux to successfully dd an image to or from RQDX3 formatted 3.5" HD floppies?

I supposed if I get sufficiently curious I could put together the pieces to try this experiment myself.

-Glen
 
No, it is not formatted as a standard PC disk. I used PUTR to format and build the disk image.

The PDP emulator in SIMH did not have the definition for the RX23, I had to add it to the rq.c file. E11 natively supports RX23. The RT11 boot disk I built with PUTR boots into E11 and SIMH now.

len


Hmm, now that I think about it, while a 3.5" drive might work fine cabled up to an M7555 RQDX3 an operating as an equivalent to an RX33 5.25" drive, there might be issues trying to exchange the floppy media between that system and a PC expecting normally formatted 3.5" floppy media.

What exactly does it mean to patch SIMH to recognize RX23's? If the 3.5" floppy media is formatted in the standard 1,440KB HD format I don't think that will really be compatible with the RQDX3 firmware.
 
PCB's are scheduled to arrive today. I should be able to let you know if it works on my '83 in a day or two.



So if you attach an RX23 to an RQDX3 and low level format an erased 3.5" HD floppy as through it were an RX33 drive and media using ZRQCH0, and then also attach the RX23 drive to a PC and low level format an erased 3.5" HD floppy there and compare the result of using ImageDisk to look at the two floppies, are the results the same except for sectors per track, 15 vs. 18, or does ImageDisk report different data rates as well?

Just because ImageDisk might be able to identify the RQDX3 low level floppy format in terms of sectors per track and data rate, if it not what is normal for a PC system would you be able to get Linux to successfully dd an image to or from RQDX3 formatted 3.5" HD floppies?

I supposed if I get sufficiently curious I could put together the pieces to try this experiment myself.

-Glen
 
Glen,

I don't remember checking the data rate, but they should both be 500kHz, because RX23 and RX33 are that anyway. The only difference is that an RX33 spins at 360RPM and RX23 at 300RPM. The ZRQCH0 formatted RX23 should just have dead space (or leftover garbage) after the 15th sector.

For the record, the other thread I referred to with the Gotek work was here: http://www.vintage-computer.com/vcforum/archive/index.php/t-41116.html

I can't comment on the linux question as I don't use it.

Lou
 
Hi All;
Lou, "" I can't comment on the linux question as I don't use it. "" I thought You would Surely have it on Your 8E..

THANK YOU Marty
 
Update!

I got rt11 booted tonight, although not on a rx23 formatted disk. I ended up reformatting to a rx33 disk and it booted. I am using a standard 3.5 inch pc drive.

When I tried booting from the rx23 I got:

Trying DU0

Starting system from DU0

005010

@

So what does that mean? Has anyone got rt11 booted from a rx23 formatted disk?

Anyway, all and all great progress.

Len
 
Back
Top