4MB jumpers and 64KZ Jumper

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Richard Muse

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Oct 26, 2020, 1:47:12 PM10/26/20
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I've attached pictures of the 4MB jumper and switch settings and the
jumper location on the 64FDC. It was necessary to use S100 pin 69 for
the RAM disable (alternate to Phantom*) to allow the copy of RDOS to ram
on boot. Pin 67, *Phantom, is used on the DPU, XPU and XXU and is
labeled memdsb* but does not function as a Phantom* line and holds pin
67 asserted.

I had to use S100 pin 69 on the 64FDC, labeled RFU3 on John's 4MB board,
to pick up the ROM enable without interference. To utilize this install
a jumper on the lower pins 7 instead of on 5 on P52 and open SW4,7
instead of SW4,5. I have found this to work with the DPU, XPU and XXU.

This board is the first 4meg. Higher addressed boards do not, of course,
need the Phantom* line.

I first tried S100 Pin 67 on the 64FDC and Phantom* enabled on the 4MB
board, but for me, the system would not boot and I found the Pin always
asserted. The above configuration works for me with all 3 680xx CPU boards.

Richard


1074.JPG
1077.JPG

randy482

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Oct 26, 2020, 2:28:12 PM10/26/20
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While I haven't looked at the XPU pin 67 should be pulled high and only pulled low (asserted) by an OC TTL device.

This allows other boards to assert (ground) so using pin 67 should be fine.


Randy

norwestrzh

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Oct 26, 2020, 3:10:33 PM10/26/20
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On Monday, October 26, 2020 at 10:47:12 AM UTC-7, rlm2667 wrote:
....<snip>....

Thanks Richard!!  Looking forward to trying this.

>> I first tried S100 Pin 67 on the 64FDC and Phantom* enabled on the 4MB 
>> board, but for me, the system would not boot and I found the Pin always 
>> asserted. The above configuration works for me with all 3 680xx CPU boards.

I can verify that this is TRUE (for the XPU anyway).  I tried it yesterday, and got "standby" on the console and then crickets.

Roger

norwestrzh

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Oct 26, 2020, 8:16:54 PM10/26/20
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>> Thanks Richard!!  Looking forward to trying this.

Made the mods. today (Monday), and it works!  A little odd here and there.  For example, when I shutdown, I can't use the reset switch and then re-boot.  Have to power the CS-1 off, let it sit for a few, and then re-start.  I'm a little surprised that I still see the "memory test" only showing 512k.  I expected to see more (with 4 MB in the bus).  Is that typical?  Is there a command to show how much available memory Cromix thinks there is?

Also discovered that my printed documentation is mostly old (newest is July 1983).  Many dated 1980!.  Lots of things in the /bin directory aren't described anywhere.  I sure miss Marcus' archive.  Could somebody give me some hints about the "ramdisk" syntax?

I get "Usage: Ramdisk {-c # | -d | -s | -r} device ..."

What are -c, -d, -s , and -r???

Roger


MikeS

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Oct 26, 2020, 10:59:53 PM10/26/20
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Hi Roger,
 
My scanner's not available at the moment so I'll send you Marcus' copy of the latest (Rev I) Cromix+ User's guide off-list; see p. 3-218
 
m
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damian

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Oct 27, 2020, 7:18:28 AM10/27/20
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Hello Roger

The amount of memory scanned at boot is set when cromix.sys is generated via /gen/sysdef

% System memory size:

        maxmem  16               % Amount of supported memory expressed
                                 % in 256K units.

The default value for maxmem is 2.

On Cromix Plus Release 162

#help ramdisk

utility:      RAMDISK
purpose:      This program creates, deletes, verifies, and calculates
              checksums on RAM disks.

user access:  privileged user

summary:      ramdisk [-c #] [-d] [-r] [-s] device-name(s)

arguments:    RAM disk device names

options:      -c #  create RAM disk of given size
              -d    delete RAM disk (return memory)
              -r    read RAM disk to show checksum errors
              -s    salvage RAM disk (recompute checksums)

Description

The Ramdisk utility should be called with one option and one or more RAM-disk
device names as arguments. Ramdisk performs different actions, depending on
the specified option.

Options
The -c option must be followed by the size of RAM disk (must be a multiple of
four) to be created. The size is expressed in K (1024 bytes). The requested
amount of memory will be allocated by the system and used as RAM disk. The
contents of RAM disk will be all zeros. The Mode utility used on such a RAM
disk will show a smaller number of available blocks, as one or more blocks,
depending on size, will be used for checksums on individual blocks.

The -d option deallocates the RAM disk created by the -c option.  The memory
occupied by the RAM disk is returned to the system's memory pool.

The -r option reads all of the RAM disk. Any checksum errors are reported on
the raw console.

The -s option recomputes all checksums. After running Ramdisk with the -s
option, the RAM disk driver will report no checksum error. Because checksum
errors should not be ignored, use the -s option with discretion.

Notes

The Mode utility, when applied to a RAM-disk device, shows various
characteristics, including the size, in blocks, and the verify flag. Although
Mode can be used to turn off the verify flag, resulting in increased speed,
this is not recommended. Turning the verify flag off defeats a valuable
checking mechanism. While the flag is off, write operations do not compute a
checksum. Thus, when the flag is turned on again, the RAM disk driver may
indicate numerous errors. (The checksums are no longer up to date.)

When using Makfs to create a file system on a RAM disk, makfs -b 2 forces the
beginning of the inode area to the block following the Superblock.  This is
acceptable because there is no need for a boot area on a RAM disk.

Example

The following example is a typical command file that creates a RAM disk, loads
it with some often-used programs, and mounts it to /ram.

ramdisk -c 128 rd0                   % Create 128K RAM disk
makfs -b 2 rd0                       % Create file structure without
                                     % boot area
mount rd0 /ram                       % Mount RAM disk
dir /bin                             % Copy useful files from /bin
copy copy.bin version.bin mode.bin ls.bin /ram
dir /cmd                             % Copy useful commands from /cmd
copy bak.cmd /ram

Execution of a similar command file might be specified in the file
startuo.cmd

Damian


Richard Muse

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Oct 27, 2020, 12:48:26 PM10/27/20
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WhooHoo!

To see all of the memory, you will have to generate a new cromix.bin with maxmem set to 16 to use all of the memory.  In the /gen directory you edit sysdef and set maxmem there. It is the first setting after the comments. Then run crogen and it will build a new cromix.sys file with the new setting. There are a lot of other provisions in that file so be careful. The sysdef for the cromix.sys you are using must have been set to 2. That's the default if I'm not mistaken.

Cromix does not do dynamic memory sizing beyond the value in sysdef. It will limit memory to what it finds in the memory test if the sysdef setting is larger than the amount installed however.

I have not experienced the reset-reboot issue.

You are going to inspire me to unpack my systems and start them back up. Moved houses a bit ago and had to pack them up.

Copy of the beginning if the default sysdef file below so you can see what I'm referring to.

I attached the default sysdef file. Line 15 is the maxmem line. Line 40 (BDEV 05 line) is the ramdisk driver. You will have to add 'ramdsk' in the 3rd field on line 40 as well as the maxmem change, then crogen a new cromix.bin to be able to use the ramdisk.

You run crogen from inside the /gen directory. The new cromix.bin will be put in the current, /gen, directory by default. You can boot to it with boot /gen/cromix to test it. I don't think you need the .sys after cromix in the boot command but don't remember exactly. Anyway, I'd do that before moving the new cromix.sys to the root. Just in case.

Richard

%       Cromix 30 System Generation file
%
%       Sep 20, 1985

% Device driver names should be entered on appropriate row. A current
% list of devices supported and their driver names can be found at
% the end of this file. Each driver can have a number of integer
% arguments. Those arguments, if any, should follow the driver name.
% The arguments must be separated by white space. The number of arguments
% and their meaning depend on the particular driver. See description
% at the end for the arguments a driver might require.

% System memory size:

    maxmem  2               % Amount of supported memory expressed
                % in 256K units.

% Character devices:

    CDEV    01      tty 0                   % FDC terminal only
    CDEV    02                              % Suggested qtty

sysdef

norwestrzh

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Oct 27, 2020, 4:27:53 PM10/27/20
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Thanks for the excellent help with understanding how Cromix handles memory, Richard.  I thought that it might check and re-size itself dynamically.  No such luck!

BUT, this opens a whole new bucket of worms.  I have to check again, but I don't remember seeing a /gen directory in any of the diskettes I have.  Soooo, I'm going to have to figure out a way to move files (after I find them *grin*) to the CS-1 from an external source.  Not as easy as it sounds.

Also, I'm kind of dead in the water anyway, because I don't have a way to edit files.  I haven't tried it, but it sounds like "screen" is set up for the proprietary Cromemco terminals?  Maybe won't work (well) with VT-100, or ANSI?  I remember seeing an application named "ed" in the bin directories, and wonder if it is a throwback to the clunky line editors of the day (ugh!), or if it is just a link to "screen"?

Maybe Cromix is just going to be a curiosity for me?  Nice to look at, but not really fully functional?

Roger

Richard Muse

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Oct 28, 2020, 10:06:37 AM10/28/20
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Roger,

Ok, I am definitely going to have to fire up my systems. Then I can build you a disk(s) with what you need.

CE is the visual editor in 68000 cromix. It uses a termcap file so can be set up to use other terminals. I have termcap definitions for it using vt100, televideo 920 (series) and a couple of others that I've tested.

You can use pccom from Cromemco to send and receive files from a pc. pccom is dos based and starts up a program in cromix to communicate with to send files back and forth. It works better with an octart intelligent port but I've been able to use it on the FDC serial port. It also has a terminal emulator. Unfortunately, it is an ansi terminal not a cromemco 3102. I have pccom and can email it to you if you want it. It will let you get files back and forth.

What are you using as a terminal?

Am I correct that you are using 51/4 HD drives? Have you set up a 3.5"HD drive to use?

Richard

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MikeS

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Oct 28, 2020, 12:59:27 PM10/28/20
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My system's up and running but I can't find my boxes of Cromemco disks; if/when I do I'll be happy to help any way I can.
 
Note that the version of CE in 31.05 is actually a preliminary version; you might do better using a later version.
 
To copy that first file from a PC to the Cromemco don't overlook Dave Dunfield's CromRT program; it's slow and only creates DD disks but it does work, creating a 'real' disk from an image on a PC using RDOS and a serial connection:
 
 
m
----- Original Message -----
Sent: Wednesday, October 28, 2020 10:06 AM
Subject: Re: 4MB jumpers and 64KZ Jumper

Richard Muse

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Oct 28, 2020, 1:42:34 PM10/28/20
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Yea, I don't remember why I made 31.05 disks for Roger.  I think it had to do with minimum memory and 31.05 either would run in less memory or maybe crogen would work in less than later versions. I may be off on that though. Now that the 4meg board is working, memory isn't an issue anymore.

Richard

MikeS

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Oct 28, 2020, 1:58:19 PM10/28/20
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More likely a question of disk space since he doesn't have a hard disk, I'm not sure how many versions could actually run on one 1.2M floppy.
 
But once Cromix is installed and configured that 4MB card should make a honkin' RAM disk.
 
m

Richard Muse

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Oct 28, 2020, 2:23:22 PM10/28/20
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So true. Even compared to the ST506 emulator, the Ram disk is much faster.

Richard

norwestrzh

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Oct 28, 2020, 3:12:53 PM10/28/20
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On Wednesday, October 28, 2020 at 9:59:27 AM UTC-7, MikeS wrote:

>> My system's up and running but I can't find my boxes of Cromemco disks; if/when I do I'll be happy to help any way I can.

You and Richard have been a great help!!  Thanks!!  I assume that the boxes of disks you are looking for have the Cromemco software on them?  I can't help there (with software), but if you give me your snail mail address, I'll send you a brand new, shrink wrapped box of HD diskettes.  Same for you, Richard.

>> To copy that first file from a PC to the Cromemco don't overlook Dave Dunfield's CromRT program; 

I think I tried that a looong time ago, and my memory of it is not a pleasant one.  Maybe I need to try again?

I'm thinking that if I can find a way to get a file onto a CDOS diskette, I could use the Cromix application to read the file??

Roger

Richard Muse

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Oct 28, 2020, 3:14:56 PM10/28/20
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Yes, you can read a cdos disk in cromix.

Richard

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MikeS

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Oct 28, 2020, 4:54:57 PM10/28/20
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----- Original Message -----
From: norwestrzh
To: Cromemco
Sent: Wednesday, October 28, 2020 3:12 PM
Subject: Re: 4MB jumpers and 64KZ Jumper


On Wednesday, October 28, 2020 at 9:59:27 AM UTC-7, MikeS wrote:


>> My system's up and running but I can't find my boxes of Cromemco disks; if/when I do I'll be happy to help any way I can.


> You and Richard have been a great help!!  Thanks!!  I assume that the boxes of disks you are looking for have the Cromemco software on them?  I can't help there (with software), but if you give me your snail mail address, I'll send you a brand new, shrink wrapped box of HD diskettes.  Same for you, Richard.
---
No need, Roger, but thanks for the offer.
==



>> To copy that first file from a PC to the Cromemco don't overlook Dave Dunfield's CromRT program;

>I think I tried that a looong time ago, and my memory of it is not a pleasant one.  Maybe I need to try again?
--
That's odd; AFAIK it works fairly well, within its limitations. We both started work on it together for a short while but as happens much too often I lost interest; as usual for Dave, he persevered and finished it.
==

>I'm thinking that if I can find a way to get a file onto a CDOS diskette, I could use the Cromix application to read the file??
--
Absolutely; the 'CDOSCOPY' program can read/write/erase etc. files on a CDOS disk. As I mentioned, most of the disk conversion programs of the day (22disk, Uniform etc.) could also read/write CDOS disks on a PC as long as it could do FM SD, but I've never seen one that could handle the Cromix format at the file level.
 
680x0 Cromix can also run many CP/M programs with the Z80 found on DPU and XPU cards. The XXU no longer has a Z80 but you can still run CP/M programs on one of the various I/O cards that have one. Unfortunately it's limited to fairly early versions of CP/M, but there are patches and alternatives out there.
 
Hang in there; once you get past the initial frustrations of transferring files, editing text and configuration files etc. you'll have lots of fun!

m



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MikeS

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Oct 28, 2020, 5:01:10 PM10/28/20
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----- Original Message -----
From: norwestrzh
To: Cromemco
Sent: Wednesday, October 28, 2020 3:12 PM
Subject: Re: 4MB jumpers and 64KZ Jumper


On Wednesday, October 28, 2020 at 9:59:27 AM UTC-7, MikeS wrote:


>> My system's up and running but I can't find my boxes of Cromemco disks; if/when I do I'll be happy to help any way I can.

> You and Richard have been a great help!!  Thanks!! 
 
Don't forget Damian and Randy ;-)
 
Did you get the copy of the Cro+ User's manual I sent you? It's a fairly late revision that probably mentions a lot of features that 31.05 didn't have; AFAIK the revision related to 31.05 is Revision 'C'.
 
Have fun!
 
m

Richard Muse

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Oct 28, 2020, 5:27:30 PM10/28/20
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I think I still have the rest of the box you sent me last time so I'm good but thanks.

Richard

On 10/28/20 2:12 PM, norwestrzh wrote:
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Roger Hanscom

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Oct 28, 2020, 10:07:18 PM10/28/20
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On Wed, Oct 28, 2020 at 1:54 PM MikeS <dm...@torfree.net> wrote:

>>  That's odd; AFAIK it (Dave Dunfield's transfer code) works fairly well, within its limitations. We both started work on it together for a
>> short while but as happens much too often I lost interest; as usual for Dave, he persevered and finished it.

As I said, it was a looong time ago.  Maybe I was just impatient?  At that time I had a PC that could handle the SD track OK, so it was a *far* easier way to go (for me anyway).  22DISK worked *very* well on that PC (for Cromemco CP/M formats -- don't think I ever tried CDOS).  Lately, I've had pretty good luck with XMODEM (Martin Eberhard's version especially) via a TUART and with a ZPU to transfer files to CP/M, so maybe I can get an XMODEM client working on either CDOS or Cromix?  Haven't really looked that far ahead .... yet.

Something sticks in my head about (maybe?) a CDOS version of XMODEM?  Maybe Martin did one?  I'll have to check into that.

>> Absolutely; the 'CDOSCOPY' program can read/write/erase etc. files on a CDOS disk. As I mentioned, most of the disk conversion programs 
>> of the day (22disk, Uniform etc.) could also read/write CDOS disks on a PC as long as it could do FM SD, but I've never seen one that could 
>> handle the Cromix format at the file level.

No surprise there!!  The Cromix file system is a completely different beast.  I doubt that ANY of the disk conversion programs back then could do anything with it.

>> Hang in there; once you get past the initial frustrations of transferring files, editing text and configuration files etc. you'll have lots of fun!

I sure hope so!

>> Don't forget Damian and Randy ;-)

Yes, of course.  Didn't mean to exclue anybody!!

>> Did you get the copy of the Cro+ User's manual I sent you? It's a fairly late revision that probably mentions
>> a lot of features that 31.05 didn't have; AFAIK the revision related to 31.05 is Revision 'C'.

Yes, very helpful.  Thanks.

Roger

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