CCS "RST ERR" when trying to boot

[pjh]

I am hoping that someone who is running a CCS system can help me. I keep getting
an RST ERR message when I attempt to Boot the system.

Over time I acquired a set of CCS cards plus a CCS Master Boot Disk. I got the
Master disk first and tested it on my 486 system. I did a CDIR /A1 A: to comfirm
that the directory was readable then I copied the files from the boot disk onto
the 486 to check that all of the files were readable. I then archived it to
Imagedisk. I then created two user disks from the image. These were read back
in to confirm no errors, especially the system tracks. The sector one contents
were compared to the CCBOOT.ASM file assembly listing to verify the CCS boot code.

I got the 2810 CPU card next and created a MOSS monitor EPROM from the listing in
the manual and confirmed that it and the monitor code worked OK. A 2065 RAM card
was eventually added to the set. Lastly, I got the 2422 FDC card. I also created
the MOSS Disk Monitor EPROM from the listing in the 2422 manual. The 2422
monitor overlays the 2810 monitor as it should and works for other commands but
when I try the (B) Boot command I get the 'RST ERR' message and the monitor returns
to the command prompt without accessing the disk.

This is the Jumper configuration I am using as best as I can interpret from the
manuals. Do these match the configuration of a running system?

Dual Shugart 801 drives jumpered according to the CCS manual

CCS 2810A Z-80 CPU

MOSS 2.2 2810 Monitor Firmware installed from the manual firmware listing.
SER EN is enabled
Addresses at system standard of 20h.
ADD MIR address mirroring is OFF.
ROM EN is enabled
WAIT is disabled since I am using a CCS Dynamic Ram card.
JUMP EN is enabled
Jump Address is F000h
2/4 MHz PIN 98 is enabled
PHANTOM is enabled
NMI is enabled
REFRESH is enabled
2/4 MHz Toggle Switch set to 4 MHz

Model 2065 64K Dynamic Memory

BANK BYTE SELECT set to D0
BANK SELECT PORT set to 40h
BLOCK SELECT JUMPERS set to ME
BANK RESET JUMPER set to ON
PHANTOM ENABLE JUMPER set to ON
CPU SELECT JUMPER set to Z80

CCS 2422 Multimode Floppy Disk Controller Rev. B

MOSS 2.2 2422 Disk Monitor Firmware installed from the manual firmware listing.
AUTO BOOT option is disabled.
With AUTO BOOT enabled, the system does nothing.
All other jumpers to factory settings.


I have gone over the listing in the 2422 manual twice to confirm I have not mis-keyed
any of the code. Is the RST ERR message a configuration issue or somethine else?
Does the 2422 Monitor listing in the manual fail to initialize a jump vector or is
this a catch-all error message for another issue?

Any help would be appreciated.

Phillip

 

[jgrant911]

Phillip,

I was searching for some CCS documentation and came across this post and wondered if you ever solved it. I know it was quite a while back but, to paraphrase the CCS Controller Unique Software manual: "A RST ERROR (Restart Error) is triggered when a program does a restart to a location without a restart handling code (a location without a Jump Vector set up during cold start initialization)".

I have a complete CCS system that I put together in 1981, used for a while, got too busy with work and family, put it in storage, hauled it out of storage a year ago and have been (mostly successfully) resurrecting it since.

Cheers!

Jim

 

[geowar1]

I have three CCS system: two with the 2810 CPU boards and one with the 2820 CPU board. I don’t use the floppy interfaces; I use the s100computers.com Dual CF/IDE board. All three systems are running modified boot ROMs and boot to CP/M 3.x. [I also have a system based on the s100computers.com Z80 SBC board and a Z280 system and a ton of Z80 SBCs (non-S100); currently building a 50 MHz eZ80F91 system.]

The most common reason for an unexpected RST instruction is executing the RST 0x38 instruction (op code: 0xFF) from uninitialized or missing memory or reading a bad or the wrong sector of a drive.

It’s been a long time since I used the CCS MOSS ROM’s so I don’t remember if you can use it to examine memory or read/write sectors. If you can I’d read in the boot sectors one by one and verify that you’re getting what you should be getting (compared against what you wrote to the floppy).

For a system that’s been sitting this long I’d suspect the read data separator (U28a) on the floppy controller has drifted off spec. (More specifically the capacitor C6, 45 pF.) You want the one-shot from pin 2 to pin 4 to be 250 nS.

Note: I’d also replace all the electrolytic capacitor’s… they don’t age well… and the liner voltage regulators with their switching regulator equivalents (like this one). They run much cooler (no heat sink required!).

Reading thru the OP’s post all his jumpers look correct (for a non-banked system)…

 

[jgrant911]

geowar1,

Not sure if the OP is still around but I appreciate your hints regarding the floppy drives. My system is working OK (including the 2 Shugart 801 drives with Rev. 25136-1 PCBs). I wasn't having problems with a RST ERROR but when I first re-started my setup I did have disk problems. It turned out to be deteriorating floppy disks. Despite being carefully stored for almost 40 years, the boot disks that I was using were the ones that had the most use when the system was new and were much more susceptible to surface erosion. Now that I've figured that out and created a new batch of boot disks from "40 year old virgin" floppies, things are running smoothly.

In order to reduce my reliance on the old 8" floppy drives I am working on installing an HxC SD Floppy Emulator. Apparently this is possible but despite a lot of information on the HxC Forum I am not there yet. I am not an expert in the details of floppy technology (more of a systems level guy) but I'm learning!

Cheers!

Jim

 

[geowar1]

I’ve used GoTek floppy emulators on OSI/C1P and TRS-80 Model 4’s… but haven’t as yet done it for my CCS systems (since I use CF/IDE drives there).