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California Computer Systems Series 2200

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  California Computer Systems Series 2200 by Bill Degnan - 02/13/2007 21:57
The CCS Series 2200 Mainframe with Jade Controller, 64K RAM, Bitstreamer II, and Morrow drive controller.


More Pictures

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  CCS 2200 Update by Bill Degnan - 01/09/2009 21:19
Power supply OK, s-100 motherboard / backplane voltage OK, Jade Z809 CPU OK, Static RAM OK.

More:
http://vintagecomputer.n...rowse_thread.cfm?id=210

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  Vector Bitstreamer II by Bill Degnan - 01/13/2009 19:20
read manual.


This Vector Graphic Bitstreamer II baud rate settings are, left to right:
Channel C - 9600
Channel B - 2400
Channel A - 1200


See also pictures of the address select jumpers, i/o jumpers (I/O H = Channel C). I set channel C to 9600 because my terminal is set to 9600b already...and the other two channels have unidentified purpose jumpers, need to look up meaning of jumper connections.

Pictures

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  Morrow DJDMA drive controller by Bill Degnan - 01/17/2009 19:24
The Morrow DJDMA drive controller Larger Image


Took one picture:
PROM VER "DJDMA 2C 81D5"

Z80 Processor
Front Middle TTL
Front Mid


I have two of these controllers, the pictured here has no modifications. The spare I have has burned out 7805's, and a lot of jumper adjustments. I will use for parts.

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  Bootstrap Loader DJ/DMA by Bill Degnan - 02/11/2009 22:20
Using Bob Grieb's Z80 ICE v 0.62 I located the bootstrap loader in memory. Here is how I did it. The controller was installed in the known-working California Computer Systems 2200 referenced on this web site.

1. Removed Z80 of the Jade CPU, and in its place inserted the Z80 ICE. Used terminal program to read output to screen.

2. Power on with ICE pre-set to EA ("cpu running") mode. Screen returns:

0000 00 D
0000 00 D
0000 00 D
INBRA Running

3. D 0000

message appears: "stop CPU to use that command"

4. Q (to stop CPU)

5. D 0000

returns:
00 3E 00 D3 08 C3 00 E8 etc. ("means jump to E800")

6. D E800

returns:
FF FF FF FF FF FF FF FF FF FF etc.

(after moving the code from E800 to another location)

7. D 0000

returns:
FF FF FF FF FF FF FF FF FF FF etc.

-----
BUT
-----

If one repeats steps 2-7 above omitting step 6, the Jade CPU does have a chance to clear the RAM from 0000, and therefore the bootstrap code for the drive controller remains intact, starting at 0038:

21 4A 00 LXI H,4A
36 MVI M,0
7E MOV A,M
B7 ORA A
CA 3D 00 JZ LOOP
FE 40 CPI 40H
C2 3D 00 JNZ LOOP
C3 80 00 JMP 80H
FF DB OFFH

Which I believe that the bootstrap checks an 8 in. drive, then for a 5 1/4"

The bottom line is that even without UART (RS232 terminal interface) I was able to confirm memory, z80 operation, and now the drive controller status.

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