CorComp disk controller access

[apersson850]

I've noticed that there are a number of qualified users hanging around here.

I've also realized that I have a package of software which is focused on disk controller access. I wrote it once to be able to make myself a working copy of disks like Miller's Graphics Explorer and Advanced Diagnostics. They were copy protected, so they weren't possible to copy with conventional means, not even by a sector copier. Thus I wrote some software to analyze and copy disks which use odd sector numbers or unformatted storage.

 

Today, in the world of simulators, this is of course more or less pointless. But I've understood that some still have working 99/4A hardware and some may be more interested in system programming than games.

 

So the question I'm posing is if there is any point at all in me spending time to copy these files to a format that can be hosted so you can see it? The assembly part of the software package concerns low level reading and writing of disk tracks and sectors. Since writing tracks is the same as formatting, there's also an application which can format disks inside the p-system environment. Originally, you had to use the Disk Manager or similar to accomplish that. There is a dformat program, that comes with the p-system, but it can't handle double density disks. Neither can it handle the different sector interlacing which is optimal for the p-system, which is faster in reading files than the normal operating system.

Then there an upper level, written in Pascal, which concerns analyzing read tracks and creating new tracks to be written (formatted). It also concerns reading and writing sectors on the disk.

 

Note that the details concern the CorComp disk controller, which is pretty similar to the one from TI, but does use a different floppy disk controller chip, so it's not identical.

Edited February 26, 2012 by apersson850

[+Ksarul]

This is actually a very good thing to preserve--there are other programs that do similar things, but none of them from a p-System environment, and none were designed to manipulate p-System volumes. The only thing that comes close is Copy-C by Christopher Winter. Note that your software is also likely to work on an Atronic controller, as a lot of software recognizes it as a CorComp controller.

[apersson850]

You misunderstood me. This program works from the p-system environment, but handles normal TI disks. I've never seens any copy-protected disks for the p-system. At least not for the TI 99/4A. The reason I wrote it in Pascal is the very convenient mapping of disk sectors and similar through Pascal's datatype record, which allows you to define any structure and give meaningful names to different parts, but still handle it as a big chunk when that's convenient.

 

My programs access the controller chip, Western Digital 2793, directly on the card, without using CorComp's drivers. The chip is a bit different than the WD 1771, which TI used in their own controller.

 

I was more curious about knowing if anyone had an interest in peeking into this kind of software. Takes a bit of detective work before you can write it.

[+Ksarul]

Actually, I did understand you, but my answer wasn't as clear as it ought to have been. As noted, if it works on CorComp controllers (not all board revisions used the 2793, I have several with the 1773 as well), it should work with the Atronic and also the BwG controllers, as they also use the 1773. I am definitely interested in the code in any event.

[apersson850]

Aha, then I understand. My CorComp (I only have one) has the 2793. Perhaps there's no important difference compared to the 1773.

All right, I'll see if I can do the work of transferring the files to a format compatible with this world...

[glefebvre]

I just picked up a CorComp 9900 Disk Controller card but it didn't come with a manual. Can someone tell me what the different DIP switch setting are? Also, when the system boots up, I see the Disk Manager on the title screen but when I select it, the disk drive turns on for a bit, then stops and after a little while the system beeps. If never enters the Disk Manager utility. I am able to format a disk with a Disk Manager cartridge (it is not the Disk Manager II cartridge) and use the disk but it's only SSSD, not DSDD like the CorComp is supposed to do.

[+Lee Stewart]

I just picked up a CorComp 9900 Disk Controller card but it didn't come with a manual. Can someone tell me what the different DIP switch setting are? Also, when the system boots up, I see the Disk Manager on the title screen but when I select it, the disk drive turns on for a bit, then stops and after a little while the system beeps. If never enters the Disk Manager utility. I am able to format a disk with a Disk Manager cartridge (it is not the Disk Manager II cartridge) and use the disk but it's only SSSD, not DSDD like the CorComp is supposed to do.

 

The manual is available here: ftp://ftp.whtech.com...rdware/CorComp/

 

The controller card is looking for the Disk Manager software on any disk in any drive. If you have three drives, you probably saw all three drive lights come on one after the other. There should have been a disk supplied with the card. I will look around for a copy of the disk.

 

...lee

[Mad Hatter]

I have a CC 9900 installed in my system which has 4 floppies. It only searches for the Corcomp disk manager software on DSK1. Unfortunately I do not have this software, and a copy I got on Whtech did not work.

 

[Edit: I take it back, I just fired up the computer and tried to access the CC Disk Manager via option 1, and it did search DSK1 followed by DSK2 and DSK3].

 

Also if you are using the Texas Instruments "Disk Manager" cart, and not "Disk Manager 2", then that could be the reason why you can only format in SSSD. The cartridge came with the side-car disk controller which was released before the expansion box. The side-car disk controller was only designed to handle SSSD. I do not have a copy of the "Disk Manager" cart so I cannot see how it operates, but it seems fair to assume that using the older version of TI Disk Manager may be why you are only able to format in SSSD.

Edited March 8, 2012 by Mad Hatter

[apersson850]

There are also two different sets of EPROMs available for the CorComp controller. The first edition had some quirks that weren't too well thought out. The second is much better.

[glefebvre]

Thanks for the info. I have Disk Manager II cartridge on the way. I'll have to check it out when I get it.

[apersson850]

It's convenient to copy that disk manager file to those disks you frequently use. Thus it's usually available when you need it.

[glefebvre]

The Disk Manager II cartridge works great with the disk controller. Where can I find a copy of the disk manager file for the CorComp disk controller and what is the name of the file?

[+Lee Stewart]

The Disk Manager II cartridge works great with the disk controller. Where can I find a copy of the disk manager file for the CorComp disk controller and what is the name of the file?

 

The file is called simply, "MANAGER". The contents of the CorComp disk are

 

	Name		Size   Type		  Attr
	---------------------------------------------------
	B/MOVEM		   1   PROGRAM	  168	 U	  
	B/MPEEK		   1   PROGRAM	   56	 U	  
	B/MPOKE		   1   PROGRAM	  127	 U	  
	B/EXEC		   1   PROGRAM	   56	 U	  
	B/VPEEK		   1   PROGRAM	  154	 P	  
	B/VPOKE		   1   PROGRAM	   71	 P	  
	B/VPOKE2	   1   PROGRAM	  165	 P	  
	B/WRTRG		   1   PROGRAM	   31	 P	  
	BASICDEMO	   4   PROGRAM	 1011	 P	  
	FORTH   	   5   DIS/FIX	   80	 P	  
	FORTHSAVE	  38   PROGRAM	 9552	 P	  
	MANAGER		  97   UNKNOWN		 P	  
	XB/EXEC		   1   PROGRAM	   84	 P	  
	XB/LOAD		   4   PROGRAM	  975	 P	  
	XB/MOVEM	   1   PROGRAM	   73	 P	  
	XB/MPEEK	   1   PROGRAM	   92	 P	  
	XB/MPOKE	   1   PROGRAM	  181	 P	  
	XB/VPEEK	   1   PROGRAM	  160	 P	
	XB/VPOKE	   1   PROGRAM	  134	 P	  
	XB/VPOKE2	   1   PROGRAM	  157	 P	  
	XB/WRTRG	   1   PROGRAM	   63	 P	  

 

PM me if you need a copy.

 

...lee

[apersson850]

I think mine is 98 sectors long, som maybe there is a newer version than the one listed above.

[+Lee Stewart]

I think mine is 98 sectors long, som maybe there is a newer version than the one listed above.

 

The file takes up 98 sectors on the disk. The first sector is the File Descriptor Record (FDR). The CorComp Disk Manager (mine is v2.3) reports it as 98 sectors in its Catalog function. Fred's TI99DIR listing is what I posted, which lists the actual file sizes (not including the FDR).

 

...lee

[apersson850]

Aha. Didn't know there was a program that forgot that the file header also requires space. Thanks!