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How to Image DG Nova 3 RDOS Disks?

Hi All;
NF6X, Some Nova 3's had a Boot Prom and some did not, I Think, on the Front Panel there might be a Switch saying Program Load, Try it and then Look at memory, but before doing that, Zero out some of lower memory 000000 to 000030, then do the program Load and then Examine '000000 and so on and see if it changed any.. Also, do the same for Your Highest memory, as I can't remember if this program loads in Low Core or High Core.. But, I think Lower Core..
If, so then, You most likely have Program Load, which means You don't need to toggle in the "Boot Program" You can just load the programs from Your PC.. Otherwise, then it needs to be entered in from the Front Panel.. In Highest Core.. The Next Program that would be a good idea to enter from the Front Panel, in fact it could be entered before you Check Your Echo Program, is the Memory Address Program, and it is small enough to enter from the Front Panel,
097-000007-02_Address_Test_1969.pdf or
097-000007-01_Address_Test.pdf..
And on Most of the Listings it also shows the Binary Listing Number as well such as 95 - 000002 for the Addresss test..
I can Try to send them to You, But Bruce and I had Problems with sending pure Binary thru email, as it either wouldn't let me send it as it might be SPAM, or it would sometimes, change a file because of internal email filters..

THANK YOU Marty
 
My machine has the program load switch, and the documentation I have indicates that once I get everything working, I would normally set the switches to 100033, hit reset, then hit program load to boot off the hard drive. The previous owner marked the switches for 100033 with a sharpie pen.

If the TTY bootstrap code is also in ROM in there, then I'll need to figure out how to set the switch register to access it instead of the hard disk bootstrap. I'll dig around to see if I've overlooked that information in the documentation that I already have…

For the tape images, maybe I can make a writeable directory for you on my Dropbox or something like that?

If you zip them up before sending them and the resulting file isn't too large, then they will probably arrive intact in my email. At work we have this obnoxious filtering that even looks inside of zip files, strips out anything that looks executable, then re-encodes the zip files. My personal email doesn't do that.
 
I've read up some more on what the program load switch does. So, it looks like I need to set the switches to the I/O device number, and also set the MSB if it's a "data channel device". Then when I hit the program load switch, the machine should load 32 bytes from that device at address 0, then jump into that code. I guess when I enter 100033, it's the disk controller card's job to supply the bootstrap code for the CPU to execute?

If I can figure out the I/O device number for the TTY, then I guess this would let me load an initial 32-byte program from my Mac to location 0, and then use that to load further code. So, I wouldn't need to toggle in the program loader, but I'd still need to load it into the machine from my Mac prior to using it to load a tape image?
 
Hi All;
NF6X, actually it is easier than You would imagine.. The last two digits are for the I/O device, so TTI is 10 and TTO is 11, just like in the Echo Program.. Yes, and No, Now that You know that You can Load Programs from Your MAC.. And Yes, You would first load in the Binary Loader, but it would use Your Program Load Switch to do that, and that one is then put into Memory, High Core, then You could Load Any of the Test programs that You think You may need.. So, Your Program Load resides at Low Core, But the Binary Loader resides at High Core, out of the way of most programs, so it doesn't get overwritten.. But, since, (I think) Correct me If I'm Wrong, You have Dynamic Ram instead of Core.. That it will get lost once You turn off the machine.. But, since You have the Program Load capability, it is easier for You to Reload it, each time You turn on the Nova 3..
I just Looked at the CD's and they are All TIF files, of the Various Manuals.. No Bin files.. I would need to look at mt old Back-up Drives, to find IF I have any Bin Files, for the DG, I should, though..

THANK YOU Marty
 
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I have some manuals that Bruce sent me, plus stuff from Bitsavers, so maybe I already have what there is to have?
 
Hi All;
NF6X, Bruce is a Really Great Guy, You will find that When He is around, he will do what ever He can for You..
When it comes to Manuals, Bruce is the one to contact..
I can still See what I have in Bin files, As I mostly have had either Generic programs, like Address Test or Memory Test #2, or specific like Nova 1200 Teletype test, or programs for the Eclipse S 130.. But, nothing for a Nova 3.. When I can find what I have I can send You Bin files to get You started, but in the End you need the Specific Nova 3 programs such a MORT for the Nova 3..
On the Switch Register just substitute 11 for 33, like 100011, instead of 100033.. That is after You get the Echo Program to work..

THANK YOU Marty
 
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I was able to toggle in the Echo program, and it appears to deposit in memory (bulb 7 is burnt out, so I can't verify that bit right now). It runs, but produces no output on TTO when I type a character on TTI. So, time for me to do some more basic debugging! It's probably time for me to learn how to hand-assemble Nova code so I can toggle in more tailored tests to figure out what is going on. Probing around that I/O card without an extender will be "fun"… :)
 
Hi All;
NF6X, The best way to probe on the I/O card without an extender, (Which are Very Rare, extenders that is), is to (For now) to remove the metal cover holding the Top of the Nova 3 together.. And as long as You don't Drop it, or seriously Bend it, it will screw back in place.. And it is also easier if You remove the Nova 3 from the Rack that it is in and place it on the/a Table.. Then remove the metal top, and take out the Card that is in the Very top slot and leave the rest of them in place.. And If I remember correctly the I/O Board will be on the top of the stack of the lower 4 cards.. Where You can more easierily get to the Ic's.. If You take the Program that I gave You earlier and change the second and following lines to Load one of the Accumulators with an Ascii "A" , then use the output part of the program, and it will continually send "A" 's to the TTO, which will show up on your scope, as you trace it out..

THANK YOU Marty
 
Hi All;
NF6X, I JUST realized, and re-took a look at Your Pictures and at Your slot line up of the Cards in the Nova 3..
For Your TTI and TTO to work, You need to swap what you have in Slot 3 and slot 4, Swap Your Memory Card and Your Cassette I/O Card.. The Cassette I/O card Needs to be in Slot 3..

(Edit) NF6X, Would You Please post some more Pictures, one with the Cable on (I Think) Slot 4 taken off, I am interested in seeing if the two Center pins are there, also on the back showing the other side (Right side) of the pins for slots 3 and 4.. I might have been Wrong, as it might be wired correctly for slot 4, which in that case then You don't need to Switch what is in slot 3 and 4.. But, I need more pictures.. As well as what pins are connected to the terminal connections and back to the Backplane, where they are connected.. The Black , White , Red and Green wires..

I'm getting out my Eclipse S 130 to compare things with..

THANK YOU Marty
 
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I think my cards are in the right slots. It's slot 4 (fourth from the bottom, that is) which has the two extra pins, one of which routes B69 over to where the cable is plugged in. I'm pretty sure that I have TTI, TTO and GND wired properly to my Mac, at least. I traced the pins to the driver and receiver on the I/O card, checked the signals with an oscilloscope, etc.

Bruce sent me some additional stuff to work with, too. I may not have time to work with it more until this weekend.
 
Hi All;
NF6X, After looking further at the documentation, I Agree with You, that after all.. They are in the correct slots !!!
Sorry, about going down a Wrong Path.. Its, been awhile since I worked on my DG stuff, and the Brain gets a little foggy !!!
"" I may not have time to work with it more until this weekend. "" OK !!
Keep me posted, and I will be more than Glad to Help, if my foot and my Brain don't get in the way of each other..

THANK YOU Marty
 
Been away for a week, looks like solid progress Mark! Folks here like Marty and Bruce are priceless.
My Nova 3 console panel (only part I have right now) is missing ALL it's bulbs (scavenged?) so there's nothing to look at for info.
 
Hi All;
FireDome, You Could Put LED's in place of the bulbs, and Then put a Dropping Resistor on the Line that feeds them..
I did this on my PDP 11/45..

THANK YOU Marty
 
Great idea Marty, do you recall what LEDs you used? Right now it's just a curiosity until I (if I ) can find more Nova 3 parts, and that's looking less & less likely, so it may end up as a display. I've thought about a random light display using something like a 555 timer and 4026 counter/driver. That's why I've been looking for a more complete DG N3 to try to re-create my old '70s lab.
RogerA
 
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Hi All;
FireDome, Just plain old Red Leds, You can of course use any color You like.. Just go down to Radio Shack and get some Packages of (I forgot how many in a Pack) 30 - 50 Various Leds, that they have..
Also, As I told NF6X, Contact Bruce Ray at WildHare Computers.. If anyone has an old Nova Chassis, and would be willing to Part with it.. Bruce would be the one to Contact.. At worst, all He can Say is I don't have any, to get rid of, but at least You tried.. And Ask about Will (I can never Remember His last name) for Shipping..
THANK YOU Marty
 
A minor update: My TTY port works!


Marty provided this program above for me to toggle in:

Hi All;
NF6X, here is your Echo program..
; Read a Character from the Keyboard
starting at address 0000
062677 I/O reset
063610 TTYRD: SKPDN TTI ; Has Character been typed ?
000377 JMP .-1 ; No, then wait
062610 DIAC 0, TTI ; Yes, then Read Character and Clear Done
; Output Character to Terminal
063511 TTYWR: SKPBZ TTO ; Is TTO Ready
000377 JMP .-1 ; No, then wait
061111 DOAS 0,TTO ; Yes, Then echo character
000372 JMP 0,3 ; Return to beginning

THANK YOU Marty

It didn't do the right thing on my system, so I began studying schematics and tracing lines on the I/O board to see if my TTY connection was correct. Then, by email, Bruce provided this program to toggle in which outputs a character defined by the switch register to TTO:

Bruce Ray said:
00000/ 062677 IORST
00001/ 060477 READS 0
00002/ 061111 DOAS 0, 11
00003/ 063611 SKPDN 11
00004/ 000777 JMP .-1
00005/ 000000 JMP 0

That did produce output on my machine. Hooray! Studying the program, I noticed that the JMP .-1 instructions were encoded differently in the two programs. The lamp behavior also didn't make sense to me in Marty's program. So, I fired up RDOS under SIMH and fumbled around until I managed to enter and assemble Marty's echo program. Here's the output listing:

Code:
  0001  ECHO  
                        .TITL   ECHO
                        .ZREL
   00000-062677 START:  IORST                   ; I/O RESET
   00001-063610 TTYRD:  SKPDN   TTI             ; HAS CHAR BEEN TYPED?
   00002-000001-        JMP     TTYRD           ; NO, THEN WAIT
   00003-060610         DIAC    0, TTI          ; READ CHAR, CLEAR DONE
   00004-063511 TTYWR:  SKPBZ   TTO             ; IS TTO READY?
   00005-000004-        JMP     TTYWR           ; NO, THEN WAIT
   00006-061111         DOAS    0, TTO          ; ECHO CHAR
   00007-000001-        JMP     TTYRD           ; DO IT ALL AGAIN
         000000-        .END    START

  0002  ECHO

This one works on my system!

I've also replaced the bad bulbs on my front panel. I used type 2187 bulbs which I ordered from McMaster-Carr. They're a little bit dimmer than the original bulbs in my machine, but now all of my lamps work. That should be helpful as I continue to diagnose my boot-up problem.

Now that my TTY port seems to be working, I can start trying out other diagnostics to see what's working and what isn't.
 
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