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PDP 11/45, Part 3

Hi All;
Or You could, get two of them , they are only about 3 thru 5 dollars each, so get one programmed at 7.3728 MHz and the other one programmed at 7.407388 MHz, that way You would be covered, and have both to experiment with.. And not have to worry about only having one or the other..

THANK YOU Marty
 
Hi All;
I have tried a memory testing program and it found an error, at about 2322, so besides doing some cleaning, what else can be done to core to hopefully fix it ?? There may be other errors.. I cleaned all of the "fingers"..
My Core Voltages are, 5.02 for +5 volts, 5.06 for -5 volts, and for +20 volts, its 21.38.. With the current Power supply I can't dial the +20 down any further, but I could go up a little to about 21.80 or there abouts.. I haven't done so, yet..
Its a DataRam DR-114 (32KX18) PN: 61402 ..

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THANK YOU Marty
 
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Hi All;
I have tried my DEC H222, but its bit 9 has problems some of the time.. Addresses 4, 12, 14, 16, 20, but not 22, where it should be, 30, 32 34, 40.. Not sure If there is a pattern or not..

THANK YOU Marty
 
Hi All;
OK, I have a choice, I can keep the 4 slot DD-11's and have 32K of working Semi-conductor memory, but it would have to be Re-loaded every time.. And have two not completely working Core Boards that can plug into it..
OR
I can change to the MF-11 9 slot which I can get 16K of Core working.. But, no Semiconductor memory..

Which would You choose ?? Please let me know, and Help me decide which way to go..

THANK YOU Marty
 
Marty said:
Hi All;
OK, I have a choice, I can keep the 4 slot DD-11's and have 32K of working Semi-conductor memory, but it would have to be Re-loaded every time.. And have two not completely working Core Boards that can plug into it..
OR
I can change to the MF-11 9 slot which I can get 16K of Core working.. But, no Semiconductor memory..

Which would You choose ?? Please let me know, and Help me decide which way to go..

THANK YOU Marty
Click to expand...

Marty it all depends on what you are going to do next.

If you are going to do rather low level hardware debugging using a diagnostic image, or simple toggle in test programs, the nonvolatile nature of of core memory might make this go a bit faster (not having to reenter the program each power cycle).

If however you want to try an run an OS (like RT11) or higher level software then the larger semiconductor memory would be more useful (however you would still need some load medium, either a disk or TU58 emulation).

Don
 
Hi All;
As always, Don, Your the Man..
Eventually, I hope to do Both.. But, first would be,
"" If you are going to do rather low level hardware debugging using a diagnostic image, or simple toggle in test programs, the nonvolatile nature of of core memory might make this go a bit faster (not having to reenter the program each power cycle). "" My Thoughts exactly ..

"" If however you want to try an run an OS (like RT11) or higher level software then the larger semiconductor memory would be more useful (however you would still need some load medium, either a disk or TU58 emulation). ""

Is there a version of RT11 out there in TU58 emulation mode ?? Like Do you have it already made up ?? I would put my Semiconductor back in Just to see an Operating System Running.. That would be a worth while test of its functionality..
I also would just love to have SOLO by Brinch Hansen on my PDP 11/45, but it is only on .dsk or.tap files, and without a working Disk Drive or Tape Drive to load it to or from, I don't know enough on how to get it to load on my System..
So, for now I would be Satisfied with RT11..

THANK YOU Marty
 
Hi All;
Tradde, was by today, He Just left, I got a Spectra 111 Board from Him.. THANK YOU Tim.. We loaded stuff on the PDP 11/45 and watched it run, Kind of like Watching Paint Dry or so I'm told.. So, I hope He had a good time..
I had to take out the Core Board and put in the Semiconductor Mostek Memory Board, it has 32K of memory to make things run..

THANK YOU Marty
 
Marty said:
Hi All;
Tradde, was by today, He Just left, I got a Spectra 111 Board from Him.. THANK YOU Tim.. We loaded stuff on the PDP 11/45 and watched it run, Kind of like Watching Paint Dry or so I'm told.. So, I hope He had a good time..
I had to take out the Core Board and put in the Semiconductor Mostek Memory Board, it has 32K of memory to make things run..
Click to expand...
I did have a good time. And it was more fun than watching paint dry.
 
Hi All;
I Had my Lamp fall off of it perch, and the Cord shorted to the -5 and 20 volt Power Supply.. After fixing the Lamp Cord, and pulling the Cards, I tested the Power supplies, and Both showed the Correct Voltage..
But after putting in the Cards, and Re-starting it, the -5, +20Volt went, So I cannot Use any Core for Now..
Everything Else Looks Ok, and is Running fine.. So, until I can get some switchers at these voltages..
It looks like there was more Damage than I thought.. It looks like it too out the USB to Serial cable, and the M7800 Card as well, I don't know about the M7856 card, yet..

THANK YOU Marty
 
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Hi All;
I Found the Problem on the M7800 Card, It Blew up an 8881 Ic , or maybe the 7400 accross from it, and the UART Ic.. There is a Trail next to the 8881 Ic of Burn smoke from the IC, and the Uart has a BIG Hole in the Middle of it..
I have looked at the M7856 and by Looks it Looks OK, I will Reset the Switches and see If it works, in Emulated ODT mode..
No Good, the M7856 isn't working either..
I now have 5 non-working Serial Boards..

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THANK YOU Marty
 
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Hi All;
Roe, The Cord, had a bare spot, possibly from a soldiering Iron burn, it shorted itself to either part of the Transformer and/or one of the wires going to a wire to the Uart via a 1488/1489 sending some kind of voltage to the Uart..

THANK YOU Marty
 
Hi All;
I have taken one of the M7800 Boards and taken out all or most of the Drivers/Receivers (380/8640's and 8881's) and will put sockets in there.. We'll see what else might need to come out, as well.. This is the old Board that wiped out the /40.. I haven't plugged it into anything as of yet.. I figure I can't ruin it any further, so even If I socket the whole thing, that would be OK..

THANK YOU Marty
 
Hi All;
I GOT one of the DL-11W Boards to Work, I have one other DL-11W Board that Doesn't Work..
And three DL-11 (M7800) Boards, none of which any work..
But, one Board is progress..
THANK YOU Marty
 
Hi All;
I Spoke tooo soon, I have Output, but No Input, the input makes it past the 1489 Translator, but not to the Uart..
So I am working on it.. There is a 74157 in between..

THANK YOU Marty
 
Hi All;
I have an update, I still Don't have an input on the one Board, but on three of the other boards , one M7856 and two M7800 Boards, when I Access it, and do an examine of Address, 177560, it shows bit 7 as on, or high.. But the one Board that works as far as output is concerned there is No high bits.. So, possibly, if I can find what is causing the bit 7 to be high, just might fix the other three boards..
That I said ""but not to the Uart.."", may not be correct, I may have a dirty Ic clip, which works some of the time and not some of the time..
THANK YOU Marty
 
Hi All;
I got all the signals going to the UART, but, no R Done coming out (pin 19), I haven't checked the Data Out lines, But a thought, I checked the Voltages on the UART, and +5 is OK, But the --12 is a bit Low, as it Reads --8.2, is that tooo Low for the UART to work ??
I was headed toward the Data Lines, starting at pin 5 thru 12..
Nothing on the Data Lines, ALL are Low (0)..
THANK YOU Marty
 
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Hi All;
I have done some more testing this morning, And I found that when the --12 volt supply isn't connected to the PDP 11/45, that it jumps back up to --12.6 volts, which most likely means that either the Power Supply can't take the Load and so drops in voltage, or that the power supply doesn't have enough amperage to keep the voltage up where it belongs, It is rated at .8 Amps.. So I will try one of my other Power Supplies and see if that brings up the voltage or if it also gets pulled down to --8 volts as well.. My other supply is Rated at 2.0 Amps..
I got the --12 volts up to -12 volts, No change in the Behaviour of the Board..
THANK YOU Marty
 
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Hi All;
A couple of things, since my last posting..
There is a Limiting Zener Diode that drops the --15 volts down to --12 volts, in the normal system.. For my system, I don't need that Diode, so I shorted it out with a wirewrap wire and two pins, so it can be changed back..
On one of my M7800 Boards I put in the 1488 and 1489 Ic's, with Sockets, but I just found that it was missing the parts for the +15 volts (+12 volts), so pin 14 of the 1488 didn't have any voltage going to it, which I can fix..

THANK YOU Marty
 
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