ROMWBW Multi-OS disk Image & Booting CP/M 3

[positron (Jose L. Collado)]

After following Wayne's updated Image Build process & instructions, I created a multi-slice disk image  (concatenating all the images available in the distribution) and wrote it to a CF card, that works perfectly. What I couldn't achieve is booting CP/M 3 or ZCPR3 from the card (first booting into CP/M 2.2 and running CPMLDR pointing to the appropriate physical disk unit, 2 in my case).

I suspect that the boot process looks for the system image present only in the first slice, so this is what's preventing my CF disk to boot CP/M 3 because I've copied the CP/M 2.2 image slice first in the series of the multi-slice disk.

Is there a way to boot from a different slice in this case ?

Cheers, JL.

[Alan Cox]

> Is there a way to boot from a different slice in this case ?

CPMLDR uses the LDRBIOS so everything it does depends upon what the
LDRBIOS you have is doing. You can do anything you want in an LDRBIOS
implementation including asking the user what disk to boot off,
scanning for a signature etc. It's entirely up to the LDRBIOS.

Personally I find it easier to implement PC partition tables in the
LDRBIOS (at least for the primary partitions) as it makes it much
easier to manage media (and you can treat 'no partition table' as
legacy CP/M 2.2 raw slices) and you can use the active partition tag
and the boot area on the media. ROMWBW leaves the right spaces free to
allow for this.

Alan

[positron (Jose L. Collado)]

Thanks Alan, I'll study the LDRBIOS code for a simple solution.

Cheers, JL

[Wayne Warthen]

On Monday, February 17, 2020 at 6:21:57 AM UTC-8, positron (Jose L. Collado) wrote:

Is there a way to boot from a different slice in this case ?

At present, the RomWBW disk boot loader only understands how to boot from the first slice on the media.  Booting from alternate slices is on the todo list.

-Wayne 

[Wayne Warthen]

I just generated a new pre-release (v2.9.2-pre.31) with support for booting from any slice.  The loader will prompt you for a slice to boot after choosing a disk unit that supports slices.

Be sure to get a new ROM image and disk images as desired.  You need both for this to work fully.

There is now a new hard disk image in the distribution called hd_combo.img.  This image has slices for all the different OS options as well as one for WordStar.

Slice 0: CP/M 2.2

Slice 1: ZSDOS 1.1

Slice 2: NZCOM

Slice 3: CP/M 3

Slice 4: ZPM3

Slice 5: WordStar 4

-Wayne

[positron (Jose L. Collado)]

Thanks again Wayne for another great update to an already extremely capable platform !  And the timing is perfect for me as I was looking to settle on a Z80/Z180 development platform for hobby use (= having fun). The SC126 + ROMWBW + z88dk combo seems like the perfect match. I previously used some FPGA designs derived from Grant Searle's Multicomp, and also Rienk Koolstra's nice SBC + Monitor ROM with CF support and multi-OS boot capability (both from retrobrewcomputers.org).

Cheers, JL.

[positron (Jose L. Collado)]

By the way, before having this new pre-release from Wayne, what I did was to simply re-arrange my multi-slice image with ZCPR3 first, then boot CP/M2.2 and run CPMLDR. It works.

Cheers, JL.

[Alan Cox]

On Tue, 18 Feb 2020, 22:19 Wayne Warthen, <wwar...@gmail.com> wrote:

I just generated a new pre-release (v2.9.2-pre.31) with support for booting from any slice.  The loader will prompt you for a slice to boot after choosing a disk unit that supports slices.

Does this need any changes or other support in other bootloaders? 

Alan

[Wayne Warthen]

Does this need any changes or other support in other bootloaders? 

No.  The user will be prompted to enter a slice number after choosing a disk unit that could support slices.  The slice entered by the user is recorded by the hardware BIOS.  Existing disk loaders will just ignore the slice value and boot from the start of the disk unit.

I had not thought about Fuzix, so I apologize.  In the case of Fuzix, I assume it is inappropriate to prompt for a slice number.  I think I could add a flag to the first sector of a disk that uses RomWBW CP/M slices.  The prompt for slices would then only be made only for such disk media.  This assume that Fuzix uses it's own version of the first disk sector -- is that true?

Thanks,

Wayne 

[Michael Dadswell]

Hi Wayne,

Couldn't wait to try this on my SC126.

 The new ROM seemed to work fine, so I imaged a Compact Flash card with the hd_combo.img using Win32DiskImager. The image writes and verifies OK, but doesn't work in the SC126. I get directory listings like this :

 B>dir c:

C: AS"   "  CO" : CL"DIR"  CO" : CO"PAR"  CO" : CR"   "  CO"

C: DD"   "  CO" : DD"Z  "  CO" : DD"Z  "  DO" : DI"X  "  CO"

C: DU"P  "  CO" : ED"   "  CO" : FD"SK8"  CO" : FL"SH "  CO"

C: LB"EXT"  CO" : LI"   "  CO" : LI"K  "  CO" : LO"D  "  CO"

C: MA"   "  CO" : MB"SIC"  CO" : NU"U  "  CO" : PI"   "  CO"

C: PM"RC "  CO" : PM"XT "  CO" : RM"C  "  CO" : ST"T  "  CO"

C: SU"MIT"  CO" : UN"RC "  CO" : UN"R  "  CO" : UN"IP "  CO"

C: XS"B  "  CO" : ZA"   "  CO" : ZD"   "  CO" : ZD"NST"  CO"

C: ZS"D  "  CO" : AS"IGN"  CO" : FA"   "  CO" : FD"   "  CO"

C: FO"MAT"  CO" : MO"E  "  CO" : OS"DR "  CO" : RT"   "  CO"

C: SU"VEY"  CO" : SY"COP"  CO" : SY"GEN"  CO" : TA"K  "  CO"

C: TI"ER "  CO" : XM"   "  CO" : IN"TES"  CO" : CP"   "  SY"

It looks like every 4th character is corrupt, and unsurprisingly,  I can't load slices. I tried two different CF cards (both 128MB Cisco labelled devices) and two CF PCBs. They were the same.

 

Then I tried an old unlabelled 64MB CF card and the directory listings were good and I can load CP/M and  ZSDOS, but slice 2 also loads ZSDOS (?). Slice 3 loads CP/M3 but complains about no CCP.COM on A:.  Slice 4 loads ZPM3 but complains about no ZCCP.COM  on A:. Slice 5 says Disk is not bootable. 

 It would be boring if everything worked first time!  :)

I've got two other Z180 systems to test with this new software when I get a bit more time. I should be able to do a lots more testing on Friday. 

 

Thanks for all your work, this is a great update. The baud rate fix alone saves me a lot of messing around.

Cheers

Mike

[Wayne Warthen]

Hi Mike,

Thanks for being an "early adopter"!  Comments below.

-Wayne

On Wednesday, February 19, 2020 at 12:02:30 PM UTC-8, Michael Dadswell wrote:

Hi Wayne,

Couldn't wait to try this on my SC126.

 The new ROM seemed to work fine, so I imaged a Compact Flash card with the hd_combo.img using Win32DiskImager. The image writes and verifies OK, but doesn't work in the SC126. I get directory listings like this :

 B>dir c:

C: AS"   "  CO" : CL"DIR"  CO" : CO"PAR"  CO" : CR"   "  CO"

C: DD"   "  CO" : DD"Z  "  CO" : DD"Z  "  DO" : DI"X  "  CO"

C: DU"P  "  CO" : ED"   "  CO" : FD"SK8"  CO" : FL"SH "  CO"

C: LB"EXT"  CO" : LI"   "  CO" : LI"K  "  CO" : LO"D  "  CO"

C: MA"   "  CO" : MB"SIC"  CO" : NU"U  "  CO" : PI"   "  CO"

C: PM"RC "  CO" : PM"XT "  CO" : RM"C  "  CO" : ST"T  "  CO"

C: SU"MIT"  CO" : UN"RC "  CO" : UN"R  "  CO" : UN"IP "  CO"

C: XS"B  "  CO" : ZA"   "  CO" : ZD"   "  CO" : ZD"NST"  CO"

C: ZS"D  "  CO" : AS"IGN"  CO" : FA"   "  CO" : FD"   "  CO"

C: FO"MAT"  CO" : MO"E  "  CO" : OS"DR "  CO" : RT"   "  CO"

C: SU"VEY"  CO" : SY"COP"  CO" : SY"GEN"  CO" : TA"K  "  CO"

C: TI"ER "  CO" : XM"   "  CO" : IN"TES"  CO" : CP"   "  SY"

It looks like every 4th character is corrupt, and unsurprisingly,  I can't load slices. I tried two different CF cards (both 128MB Cisco labelled devices) and two CF PCBs. They were the same.

I can only assume this is another instance of the CF Adapter issues.  I definitely get this type of behavior depending on what slot my CF module is plugged into and/or the specific CF card I use.

  

Then I tried an old unlabelled 64MB CF card and the directory listings were good and I can load CP/M and  ZSDOS, but slice 2 also loads ZSDOS (?). Slice 3 loads CP/M3 but complains about no CCP.COM on A:.  Slice 4 loads ZPM3 but complains about no ZCCP.COM  on A:. Slice 5 says Disk is not bootable. 

Slice 2 is NZCOM.  NZCOM cannot be booted directly (that is how it is designed).  You must launch it from an existing command line.  So, when you choose slice 2, you are seeing ZSDOS load (which is intended), but the directory contents are the NZCOM distribution.  You start NZCOM, but running the command NZCOM.  WARNING: you must run a simple configuration tool called MKZCOM before you can launch NZCOM.  Please take a look at the NZCOM documentation in the Doc directory.  Once you get NZCOM working, you can add a PROFILE.SUB file to make it start automatically.

Regarding Slice 3 & 4 (CPM3 and ZPM3)... how many hard disk units are active on your system?  There is a subtle constraint here that I will try to explain.  When you choose a slice to start from, the booting OS will attempt to find a drive letter that matches the disk unit/slice being booted.  However, what if you pick a slice that is not assigned to a drive letter?  At the moment, the code just bails out and defaults to A:.  If this happens with CPM3 or ZPM3, they fail looking for the command processor file (CCP.COM or ZCCP.COM).  Ugh.  Most people are running with a single hard disk unit, so 8 slices of that unit are assigned to drives meaning that you could boot from slices 0-7 just fine.  Back to my initial question about the number of hard disk units on your system.  If you have 2 or more, then the number of drive letters assigned per unit goes down.  Boot ZSDOS from ROM.  At boot, notice the drive letter assignments.  If there are no drive letters assigned to slice 3 or 4 of the "combo" CF Card, then you will see the error you describe.  I am working on a fix for this situation, but it is, well, hard.

Finally, on slice 5, WordStar is not an OS and has no ability to boot.  It is not intended to be a bootable slice.

 It would be boring if everything worked first time!  :)

Agreed!  However, you might be in better shape than you think.  If it is a drive letter assignment issue, can you temporarily remove all hard disk media other than the combo CF card and boot that way?  In that case, you should get 8 drive letters all assigned to the one CF card and all the boot scenarios should work.

[Alan Cox]

> No. The user will be prompted to enter a slice number after choosing a disk unit that could support slices. The slice entered by the user is recorded by the hardware BIOS. Existing disk loaders will just ignore the slice value and boot from the start of the disk unit.

Ok

> I had not thought about Fuzix, so I apologize. In the case of Fuzix, I assume it is inappropriate to prompt for a slice number. I think I could add a flag to the first sector of a disk that uses RomWBW CP/M slices. The prompt for slices would then only be made only for such disk media. This assume that Fuzix uses it's own version of the first disk sector -- is that true?

Fuzix uses its own boot loader and uses PC partition table format (or
optionally GPT) so I'm sure how a slice would be meaningful there.
However I am not sure not prompting is the right thing to do. It's
possible to construct a partition table with some slices unavailable
and mix the slices and partitions, and in that case if Fuzix is first
then CP/M on other slices is still meaningful.

Maybe check each slice for the right magic numbers and only prompt if
more than one of them is bootable ?

Alan

[Scott Lawrence]

Can CP/M 2 executables be run on CP/M 3?

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[Wayne Warthen]

On Wednesday, February 19, 2020 at 1:08:02 PM UTC-8, Scott Lawrence wrote:

Can CP/M 2 executables be run on CP/M 3?

Generally, yes.  There are certainly some tools that are very tied to the OS and they might have issues, but most general purpose apps work on either. 

[positron (Jose L. Collado)]

Hi Wayne, just finished my test; results below slightly different than Mike's: no DIR errors, CP/M 2.2 and ZSDOS booted OK, CP/M 3 gave the error below.

I can confirm that the slices tested all had active drive assignments: IDE0:0 to IDE0:3 as C: to F:, so it's strange that CP/M 3 (slice 3, drive F:) boot failed with the NO CCP.COM error...

================

C>assign

   A:=MD1:0

   B:=MD0:0

   C:=IDE0:0

   D:=IDE0:1

   E:=IDE0:2

   F:=IDE0:3

   G:=SD0:0

   H:=SD0:1

   I:=SD0:2

   J:=SD0:3

================

Boot from slices 0, 1, 2 --> OK

===========================================

Boot from slice 3 --> FAILED

===========================================

CP/M V3.0 Loader

Copyright (C) 1998, Caldera Inc.

 BNKBIOS3 SPR  F800  0600

 BNKBIOS3 SPR  5200  2E00

 RESBDOS3 SPR  F200  0600

 BNKBDOS3 SPR  2400  2E00

 60K TPA

CP/M v3.0 [BANKED] on HBIOS v2.9.2-pre.31

BIOS Err on A: No CCP.COM file

==========================================

Hope this helps.

Cheers, JL.

[Wayne Warthen]

Thanks for testing Jose.  I admit I am perplexed.  I am positive CP/M boot was working for me.  I wonder if I screwed up the latest pre-release.

Anyway, I spent the day today improving the drive assignment code so that whatever slice is chosen for boot is automatically mapped to drive A:.  This eliminates the whole issue of not matching a drive letter.

I don't want to cause any further grief, so I am going to spend a day or two testing this before I post it.

Thanks,

Wayne

[Jose Luis Collado]

Hi Wayne, no grief here; I'll be glad to beta-test your changes before you publish them, and sending the results. My platform is SC-126 with both SD & CF Cards. Have a batch of Sandisk & Cisco 512 MB "well behaving" CF cards to test with, and transfer the .COM versions of updated ROMs to test in RAM (they go to the SD card, so I have the CF free for new images to test).

Just tell me where to get the code.

Cheers, JL.

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[Wayne Warthen]

On Thursday, February 20, 2020 at 4:04:37 AM UTC-8, positron (Jose L. Collado) wrote:

Hi Wayne, no grief here; I'll be glad to beta-test your changes before you publish them, and sending the results. My platform is SC-126 with both SD & CF Cards. Have a batch of Sandisk & Cisco 512 MB "well behaving" CF cards to test with, and transfer the .COM versions of updated ROMs to test in RAM (they go to the SD card, so I have the CF free for new images to test).

Just tell me where to get the code.

Cheers, JL.

Thank you.  I expect to post some source updates late today.  For what it is worth, I finally managed to recreate your error -- a very subtle problem with the drive letter assignment logic.

Thanks,

Wayne

[Wayne Warthen]

OK, as promised, I have posted new code that resolves the boot issue reported previously.  Additionally, this release completely eliminates the problem with drive assignment matching for some slices.  Whatever slice is chosen for boot is automatically mapped to A:.  The other drive letters are "pushed" as needed.

Many CP/M era OSes really do not like booting from a drive letter other than A:.  This change ensures that whatever you boot becomes drive A: and things just seem to work better (ZSDOS paths, etc.).

After booting, pay attention to the slice assignments.  ZSDOS and CP/M 2.2 will automatically display the slice assignments at boot.  For CP/M 3 and ZPM3, just use the ASSIGN command with no parameters to display the current drive assignments.

I tested this pre-release a little more thoroughly than usual and I am pretty confident it is reliable.  This is a full pre-release with all the pre-built binaries.  See GitHub for v2.9.2-pre.32.  Be sure to update your ROM first, make sure you can do ROM boots, then you can try the disk images.  The hd_combo.img image is working nicely for me and I find it very cool to be able to boot any of 5 OSes easily from one media.

The ASSIGN command is, of course, still available to tweak your drive assignments after boot.

Thanks,

Wayne

[positron (Jose L. Collado)]

Brilliant Wayne, worked perfectly ! Many thanks for another great ROMWBW update !!! I sense more comming soon... (Play... User ROM... ;-)

Cheers, JL.

[Wayne Warthen]

On Friday, February 21, 2020 at 5:49:40 PM UTC-8, positron (Jose L. Collado) wrote:

Brilliant Wayne, worked perfectly ! Many thanks for another great ROMWBW update !!! I sense more comming soon... (Play... User ROM... ;-)

I'm pleased to hear it is working for you.  Thanks for testing.

 

[Colin Little]

Yes, an excellent update. I'm using a floppy disk emulator, CF drive and SDcard on my SC126. All storage items working on all slices i.e, known slices!!!)

[Jay Cotton]

Hi Wayne:

I just did an update to latest and thud.  No console to the KIO port.  I used my (older) kio config file.  Should I be looking at

a different configuration ?   I'll try bone stock now.

jc

[Jay Cotton]

Ok the bone stock config works.

now to add SD and Spinning rust.

jc

[Wayne Warthen]

Hi Jay,

Glad the stock config worked, but I'm surprised you had trouble initially.  I specifically tested RCZ80 w./ KIO and WizNet.

Can you send me the config file you used that did not work?  I want to see the differences between that and my test config.

Thanks,

Wayne

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[Jay Cotton]

Hi Wayne:

Here is the config file that attempted to use.I got an error with this file and commented out

IDEMODE.

jc

;

;==================================================================================================

;   RC2014 Z80 STANDARD CONFIGURATION W/ KIO

;==================================================================================================

;

; THE COMPLETE SET OF DEFAULT CONFIGURATION SETTINGS FOR THIS PLATFORM ARE FOUND IN THE

; CFG_<PLT>.ASM INCLUDED FILE WHICH IS FOUND IN THE PARENT DIRECTORY.  THIS FILE CONTAINS

; COMMON CONFIGURATION SETTINGS THAT OVERRIDE THE DEFAULTS.  IT IS INTENDED THAT YOU MAKE

; YOUR CUSTOMIZATIONS IN THIS FILE AND JUST INHERIT ALL OTHER SETTINGS FROM THE DEFAULTS.

; EVEN BETTER, YOU CAN MAKE A COPY OF THIS FILE WITH A NAME LIKE <PLT>_XXX.ASM AND SPECIFY

; YOUR FILE IN THE BUILD PROCESS.

;

; THE SETTINGS BELOW ARE THE SETTINGS THAT ARE MOST COMMONLY MODIFIED FOR THIS PLATFORM.

; MANY OF THEM ARE EQUAL TO THE SETTINGS IN THE INCLUDED FILE, SO THEY DON'T REALLY DO

; ANYTHING AS IS.  THEY ARE LISTED HERE TO MAKE IT EASY FOR YOU TO ADJUST THE MOST COMMON

; SETTINGS.

;

; N.B., SINCE THE SETTINGS BELOW ARE REDEFINING VALUES ALREADY SET IN THE INCLUDED FILE,

; TASM INSISTS THAT YOU USE THE .SET OPERATOR AND NOT THE .EQU OPERATOR BELOW. ATTEMPTING

; TO REDEFINE A VALUE WITH .EQU BELOW WILL CAUSE TASM ERRORS!

;

; PLEASE REFER TO THE CUSTOM BUILD INSTRUCTIONS (README.TXT) IN THE SOURCE DIRECTORY (TWO

; DIRECTORIES ABOVE THIS ONE).

;

#include "cfg_rcz80.asm"

;

CPUOSC .SET 7372800 ; CPU OSC FREQ IN MHZ

INTMODE .SET 2 ; INTERRUPTS: 0=NONE, 1=MODE 1, 2=MODE 2

DEFSERCFG .SET SER_115200_8N1 ; DEFAULT SERIAL LINE CONFIG (SEE STD.ASM)

;

KIOENABLE .SET TRUE ; ENABLE ZILOG KIO SUPPORT

;

CTCENABLE .SET TRUE ; ENABLE ZILOG CTC SUPPORT

CTCBASE .SET KIOBASE+$04 ; CTC BASE I/O ADDRESS

;

ACIAENABLE .SET FALSE ; ACIA: ENABLE MOTOROLA 6850 ACIA DRIVER (ACIA.ASM)

;

SIOENABLE .SET TRUE ; SIO: ENABLE ZILOG SIO SERIAL DRIVER (SIO.ASM)

SIOCNT .SET 1 ; SIO: NUMBER OF CHIPS TO DETECT (1-2), 2 CHANNELS PER CHIP

SIO0MODE .SET SIOMODE_EZZ80 ; SIO 0: CHIP TYPE: SIOMODE_[RC|SMB|ZP|EZZ80]

SIO0BASE .SET KIOBASE+$08 ; SIO 0: REGISTERS BASE ADR

SIO0ACLK .SET 1843200 ; SIO 0A: OSC FREQ IN HZ, ZP=2457600/4915200, RC/SMB=7372800

SIO0BCLK .SET 1843200 ; SIO 0B: OSC FREQ IN HZ, ZP=2457600/4915200, RC/SMB=7372800

;SIO0ACFG .SET SER_115200_8N1 ; SIO 0A: SERIAL LINE CONFIG

;SIO0BCFG .SET SER_115200_8N1 ; SIO 0B: SERIAL LINE CONFIG

;

FDENABLE .SET FALSE ; FD: ENABLE FLOPPY DISK DRIVER (FD.ASM)

FDMODE .SET FDMODE_RCWDC ; FD: DRIVER MODE: FDMODE_[DIO|ZETA|DIDE|N8|DIO3]

;

IDEENABLE .SET TRUE ; IDE: ENABLE IDE DISK DRIVER (IDE.ASM)

IDEMODE .SET IDEMODE_RC ; IDE: DRIVER MODE: IDEMODE_[DIO|DIDE]

;

PPIDEENABLE .SET TRUE ; PPIDE: ENABLE PARALLEL PORT IDE DISK DRIVER (PPIDE.ASM)

SDENABLE .SET TRUE

SDMODE .SET SDMODE_MT

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[Wayne Warthen]

Thanks Jay.  I will play with this.

-Wayne

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[Wayne Warthen]

Hi Jay,

I tracked down the issue with the config file below.  The newer SIO driver config adds a configuration line to specify the CTC Channel to use as the baud rate scaler for SIO.  I think you have jumpered your module like me to use CTCA as the baud rate scaler.  You just need to add a line like the following and it will work:

SIO0CTCC .SET 0

This indicates that CTC channel 0 (i.e., A) should be programmed as the prescaler.

Thanks,

Wayne

[Jay Cotton]

Ah, thanks for looking into that Wayne.

I have a new problem, I'll start another thread for that one.

tnx

jc