View Full Version : Jade Double D System boot problem.

December 21st, 2016, 05:59 PM
Has anyone had any problems getting a Jade System to boot with the
disk created from the JADEDD.IMD file from Dave Dunfield's website.
After the startup/reset, the signon message appears:

Jade Computer Products
20k CP/M 2.2 DDBIOS2

Eight to ten seconds later an error message appears:

CCP/BDOS load error

The DDBOOT is appearently reading the DDBIOS off of Track 0 and
passing control to it. The DDBIOS then is suppose to read the
CCP/BDOS data off of Track 1, but instead I get the above error
message. Is this a problem with the .IMD file or is there a
configuration setup that can cause the above error?

I am using these cards from my monitor system for the test bootup:

A Dual Systems32k Static Ram so I have memory of sufficient size.
An Ithaca MPU80 processor card set to 4mHz
An Ithaca VIO serial/parallel card
An Ithaca Eprom card with the DDBOOT file modified to use the
Ithaca VIO card as the console.

Also, I am using the Jade Double D Disk Controller Card (Revision B)
bought off of eBay with all of the modifications of the 'artwork'
made as described in Appendix E of the manual. All of the
appropriate traces had been cut and the correct components added.

All of the jumpers and switch settings for the Jade system were already
made. Switch 1 on the Double D board is set like this:

1 - Off
2 - Off
3 - On
4 - Off
5 - On
6 - On
7 - Off
8 - Off

The jumpers and these switch settings seemed to be correct as I
interpreted the setup so I left them as is.

Any help would be appreciated,


December 26th, 2016, 06:17 PM
Hello Phillip, I have the Jade DD disk controller but have not yet got it working. Lately I have been working on getting a reliable floppy disk drive as my old 8" drives may or may not be working well. I have invested some time using Dave Dunfields Image Disk Program and created a real disk from the JadeDD disk image on his site. The process worked without any errors and I was able to re-save the physical disk back to an Image File again with no errors. I can do a directory listing on the physical Jade DD disk but cannot boot from it as I don't have the Jade DD card working. I tried modifing the DDBoot.asm file and burning an EPROM for the CPU card but was not able to get anything working with the Jade DD controller card. This will require much more time and effort on my part but I think the Image Disk file is good. Maybe someone else has got the Jade DD working.



December 26th, 2016, 07:47 PM
Hi Charles,

I too have used Image Disk and have created several other disks from the images with much success. Every new disk I create, I then turn around and use the CTOD command from 22disk to copy the files into an archive directory on my 486 system. I have had a few instances where an individual file was unreadable on the created disk but I am sure that is because the original disk used for the image also had a bad file on it. I am confident in the ability of Image Disk to create a physical disk that accurately matches the disk the image was made from.

As to your DD controller card, I have managed to refurbish several cards by testing and replacing the bad TTL chips. I use Experimeter strips with a 5 volt power supply and configure the inputs either high or low and placing LEDs on the outputs to check for correct function. I also have a 555 timer configured for about a one second pulse to use as an input to apply an
alternating input when I need it. It may take an evening or two depending on the number of chips to test, but to me it is much easier that trying to locate and trace logic errors one chip at a time since my diagnostic skills are mediocre at best.


December 27th, 2016, 02:39 AM
Here is info from the header of the image:

Track 1 on this disk contains 50 128 byte DD sectors.
128 byte DD is not supported by the 765, and very few
PCs can read/write this track.

I wonder if track 1 got transferred to your floppy correctly ?

Larry G

December 27th, 2016, 05:04 AM
Hi Larry,

Your are right. The IMD software shows no errors on the disk create. But when I re-imaged the physical disk created from the JADEDD.IMD file, the IMD header message:

I/O: 500K DD - 50 sectors of 128 Bytes - G1:7 G2:13

for track 1 displayed correctly but the read of each sector gave this error message:

Read error (xx) NoAdrMark - Unavailable

where the (xx) represented each sector number as it tried to read it.

So, it appears that I am stuck with no way to create a valid Jade DD boot disk. Thanks for the heads up on the sector 1. I was scratching my head trying to figure out what was wrong since I had had no problems with the Image Disk software before.


March 5th, 2017, 03:07 PM
This is a continuation of an old thread on the Jade Computer DD Floppy Controller board and whether or not it would work with the "IMD" Disk Image from Dave Dunfields site. After much trial and error and fiddling, yes the Jade Board will work with the [IMD 85k Jade Double-D S100 controller CP/M] from Daves site. The key to creating a working disk is to use a floppy card based on the "National Semiconductor DP8473 chip". Adaptec AHA-1520A or the DTK PII-151B floppy controller boards are two such boards that use this chip. After the disk has been created, the DD Card must be set up. There is a boot file called DDBOOT.ASM that has the program for the boot EPROM. The code should be examined to see what I/O port the software uses (Port 43H) and what address range the on-board RAM will use to communicate with the host computer (E000H). The Console Data/Status Port values must be modified to match the host computer and the NOP's should be edited out. The EPROM should be assembled at (F000H) on a 2716 EPROM. The Jade Board has only one DIP configuration switch and it should be set to match the Boot EPROM. The DIP is "CLOSED" when the switch is pushed down on the "+" side. The settings are as folows- DIP(1-8): P0=0 P1=0 U0=C U1=0 M11=0 M12=0 M13=0 TST=0 The memory card used in the system should be 32K Static RAM if you have it. The CPU card should have a POJ to (F000H) at startup. The Disk Drive used was a Shugart 851 8" Drive. Other Drives may require modding the Motor-On signal. If everything else is correct, the system should boot directly into CP/M 2.2 as soon as the computer boots. Problems may be encountered if 64K RAM cards are used (Phantom must be fiddled with). The main Engineering Modification that must be done to the Jade DD board rev. C would be the ENG#3 "SWO*" mod, nothing worked until I applied that modification. Hope this helps anyone trying to bring up a Jade DD board.




EDIT: The Memory Window on the DIP switch was not correct...This should be the correct Memory Windoe settings listed below.

March 28th, 2017, 12:30 PM
S-U-C-C-E-S-S !!!

I now have a working Jade Double D CP/M 2.2 system. While working
on another project, I came across a box of floppy disk controller
cards that I had not originally tested. I got out my 486 system and
used Dave Dunfield's TESTFDC program to check the cards.

I found a SEAGATE floppy disk controller card (ST07A/08A) that passed
the 128 byte test and then created a disk from the JADEDD.IMD file.
To confirm that it was created correctly, I then read it back into a
test file and saw that there were no errors on the track 1 read.

The included picture shows the results. I can now boot Jade CP/M 2.2