Re: PDP-12 Restoration at the RICM

On 06/05/2016 09:54 AM, Michael Thompson wrote: We fixed the RK05 disk this week. We replaced E3 (LM301A) and E1 (SN7404) on the G938 Servo Preamp module. The COUNT PULSE FWD H and the COUNT PULSE REV H signals from the G938 module are both working now. The drive will now seek correctly using the

PDP-12 Restoration at the RICM

We fixed the RK05 disk this week. We replaced E3 (LM301A) and E1 (SN7404) on the G938 Servo Preamp module. The COUNT PULSE FWD H and the COUNT PULSE REV H signals from the G938 module are both working now. The drive will now seek correctly using the jumpers described in the Maintenance Manual or us

PDP-12 Restoration at the RICM

We are now working on the RK8F controller and RK05 drive. The RK8F has special M7104 and M7105 boards so it will work in the DW8E Omnibus-Posibus chassis. The MAINDEC-08-DHRKA RK8E Diskless Control Test showed that a data-break to address worked, but did not work to address . After about

PDP-12 Restoration at the RICM

As a final diagnostic on the PDP-12 we tried to run FOCAL-69, but it started executing instructions in non existent memory. FOCAL initializes lots of peripherals and then tries different instructions to determine what processor it is running on. It executed what it thought was a TC01 DECtape IOT, b

Re: PDP-12 Restoration at the RICM

On Tue, Dec 22, 2015 at 08:31:46PM -0500, Michael Thompson wrote: > the [paper tape] reader does not always step correctly and does not > read the tape correctly. Ah, then you have restored it to as-shipped condition :-) mcl

Re: PDP-12 Restoration at the RICM

On Thu, Dec 24, 2015 at 9:59 AM, Michael Thompson < michael.99.thomp...@gmail.com> wrote: > > Kyle's SerialDisk is here: https://github.com/drovak/os8diskserver I just pushed some changes earlier. Hopefully I didn't break too many things! :) The system handler now has support for FRTS. Still nee

Re: PDP-12 Restoration at the RICM

On 2015-Dec-24, at 1:58 PM, Jon Elson wrote: > On 12/24/2015 01:22 PM, Jay Jaeger wrote: >> On 12/24/2015 9:59 AM, Michael Thompson wrote: >> >>> We have been able to fix all types of broken flip-chips. Sourcing the >>> components is sometimes a challenge. The Germanium transistors for the TU20 >>

Re: PDP-12 Restoration at the RICM

On 12/24/2015 01:22 PM, Jay Jaeger wrote: On 12/24/2015 9:59 AM, Michael Thompson wrote: We have been able to fix all types of broken flip-chips. Sourcing the components is sometimes a challenge. The Germanium transistors for the TU20 on the PDP-9 were hard to find. I remember replacing a ger

Re: PDP-12 Restoration at the RICM

On 12/24/2015 9:59 AM, Michael Thompson wrote: > > We have been able to fix all types of broken flip-chips. Sourcing the > components is sometimes a challenge. The Germanium transistors for the TU20 > on the PDP-9 were hard to find. > I remember replacing a germanium (at least I think it was) t

Re: PDP-12 Restoration at the RICM

> > Date: Tue, 22 Dec 2015 20:56:51 -0600 > From: Jay Jaeger > Subject: Re: PDP-12 Restoration at the RICM > Message-ID: <567a0d73.2010...@charter.net> > Content-Type: text/plain; charset=utf-8 > > I have an image of MAINDEC-12-D8CD-PB, and a listing as well >

PDP-12 Restoration at the RICM

Lots more work on the PDP-12 at the RICM. We got an RS-232 console board and baud rate generator from Vincent and now have both serial ports working. Warren modified Kyle's SerialDisk and we booted OS/8 from an emulated RK05 on the second serial port. We fixed one of the bus interface boards in the

Re: PDP-12 Restoration at the RICM

On 12/22/2015 7:31 PM, Michael Thompson wrote: > Lots more work on the PDP-12 at the RICM. We got an RS-232 console board > and baud rate generator from Vincent and now have both serial ports > working. Warren modified Kyle's SerialDisk and we booted OS/8 from an > emulated RK05 on the second seri

Re: PDP-12 Restoration at the RICM

I used my PDP-8/e at home to test the RX8E controller and the RX01 floppies that came with the PDP-12. Both worked OK. We found a bad SP380 on a M7102 board in the DW8E the Omnibus expansion chassis. This would not let the SKIP instructions work with the RX8E, RK05, or PC8E. Once we replaced the S

Re: PDP-12 Restoration at the RICM (tony duell)

On Tue, Oct 13, 2015 at 08:32:49PM -0400, Michael Thompson wrote: > > What exactly do you mean by 'glitches'? Are these on a TTL level signal, > > an analogue > > output of the read amplifer, or what? > > > > You can see the logic analyzer trace of many of the TC12 signals here. >

Re: PDP-12 Restoration at the RICM (tony duell)

On 10/13/2015 07:32 PM, Michael Thompson wrote: Tracks 1 & 2 look fine. We swapped the probes for track 2 & 3 just to make sure that it wasn't a logic analyzer problem. A 'scope connected to the differential signals shows the same track 3 glitches. The glitches were present with the TU55 and th

RE: PDP-12 Restoration at the RICM (tony duell)

> > Date: Mon, 12 Oct 2015 18:29:11 + > From: tony duell > Subject: RE: PDP-12 Restoration at the RICM > > > We swapped the TU56 and TU55 drives between the PDP-12 and the PDP-8/I. > We > > Does the TU55 work correctly on the 8/I ? > Yes, it works perfectly.

RE: PDP-12 Restoration at the RICM

From: Paul Koning Sent: Tuesday, October 13, 2015 7:55 AM >> On Oct 12, 2015, at 9:16 PM, Rich Alderson > >> wrote: >> ... >> The M tracks are longitudinally encoded (6-bit values chosen such that >> they read the same as NRZ backwards and forwards for DECtape, 4-bit >> values for LINCtape) to pr

Re: PDP-12 Restoration at the RICM

On 2015-10-13 16:54, Paul Koning wrote: On Oct 12, 2015, at 9:16 PM, Rich Alderson wrote: ... The M tracks are longitudinally encoded (6-bit values chosen such that they read the same as NRZ backwards and forwards for DECtape, 4-bit values for LINCtape) to predefine blocks (cf. disk sectors)

Re: PDP-12 Restoration at the RICM

On Tue, Oct 13, 2015 at 11:16:54AM -0400, william degnan wrote: > Did you ever speak with anyone at System Source (Bob) about their PDP 12? > Maybe they'd be interested in collaborating. http://museum.syssrc.com/ I highly recommend everyone pull up the Univac 490 (1963) page and look in the "gall

Re: PDP-12 Restoration at the RICM

Did you ever speak with anyone at System Source (Bob) about their PDP 12? Maybe they'd be interested in collaborating. http://museum.syssrc.com/ On Tue, Oct 13, 2015 at 10:54 AM, Paul Koning wrote: > > > On Oct 12, 2015, at 9:16 PM, Rich Alderson > wrote: > > > > ... > > The M tracks are longi

Re: PDP-12 Restoration at the RICM

> On Oct 12, 2015, at 9:16 PM, Rich Alderson > wrote: > > ... > The M tracks are longitudinally encoded (6-bit values chosen such that they > read the same as NRZ backwards and forwards for DECtape, 4-bit values for > LINCtape) to predefine blocks (cf. disk sectors) for data. More precisely: i

RE: PDP-12 Restoration at the RICM

From: tony duell Sent: Monday, October 12, 2015 11:29 AM >> We swapped the TU56 and TU55 drives between the PDP-12 and the PDP-8/I. We > Does the TU55 work correctly on the 8/I ? >> The TU55 behaved a little better than the TU56, and sometimes would actually >> boot OS/8. We continued chasing t

Re: PDP-12 Restoration at the RICM

On 10/12/2015 12:40 PM, Michael Thompson wrote: >> >> Date: Sun, 11 Oct 2015 18:44:54 -0500 >> From: Jay Jaeger >> Subject: Re: PDP-12 Restoration at the RICM >> >> Don't forget about the other more remote possibilities: cables, >> backplane, bad

RE: PDP-12 Restoration at the RICM

> We swapped the TU56 and TU55 drives between the PDP-12 and the PDP-8/I. We Does the TU55 work correctly on the 8/I ? > The TU55 behaved a little better than the TU56, and sometimes would > actually boot OS/8. We continued chasing the issue and found glitches on > data channel 3. We have swappe

Re: PDP-12 Restoration at the RICM

> > Date: Sun, 11 Oct 2015 18:44:54 -0500 > From: Jay Jaeger > Subject: Re: PDP-12 Restoration at the RICM > > Don't forget about the other more remote possibilities: cables, > backplane, bad wrap, supply voltages at the actual card(s) for the > mis-behaving cha

Re: PDP-12 Restoration at the RICM

I have no constructive input to share - except the strong memory of the bloke who maintained my pdp-12s for 25 years before I collected them saying that the TC12 was an "absolute bugger" and the hardest part of the machine to troubleshoot! Good luck and don't feel bad about having a hard time with

Re: PDP-12 Restoration at the RICM

On 10/11/2015 9:42 AM, Michael Thompson wrote: > > We are running out of things to try for debugging the TC12 controller in > the PDP-12. At this point we are really stumped as to why the TC12 doesn't > work correctly. We are going to try a few remaining ideas like running the > TC12 from a labora

Re: PDP-12 Restoration at the RICM

On 11 October 2015 at 10:42, Michael Thompson wrote: > We are running out of things to try for debugging the TC12 controller in > the PDP-12. At this point we are really stumped as to why the TC12 doesn't > work correctly. We are going to try a few remaining ideas like running the > TC12 from a la

Re: PDP-12 Restoration at the RICM

We swapped the TU56 and TU55 drives between the PDP-12 and the PDP-8/I. We found that the TU56 uses a double-sided paddle card for the control signals and the TU55 uses a single-sided paddle-card. The TC12 tape controller in the PDP-12 will work with either tape drive if you have the right cable. W

PDP-12 Restoration at the RICM

The Maintenance Manual-II describes the procedures for checking and adjusting the TC12 timing. It needs a lot more notes about using the Auto Restart speed settings. This facility allows you to put the processor in Single Step and have the Continue button automatically pressed ad a controllable rat

Re: PDP-12 Restoration at the RICM

On 8/17/2015 1:51 PM, Rich Alderson wrote: > From: Jay Jaeger > Sent: Sunday, August 16, 2015 3:18 PM > > On 8/16/2015 9:00 AM, Michael Thompson wrote: > >>> We did a lot more debugging on the TC12 LINCtape controller. > >> Second gut hunch is that it would be hard to see how the drive could >>

RE: PDP-12 Restoration at the RICM

From: Jay Jaeger Sent: Sunday, August 16, 2015 3:18 PM On 8/16/2015 9:00 AM, Michael Thompson wrote: >> We did a lot more debugging on the TC12 LINCtape controller. > Second gut hunch is that it would be hard to see how the drive could > cause this UNLESS the TC12 uses one side of the redundant

Re: PDP-12 Restoration at the RICM

On 8/16/2015 9:00 AM, Michael Thompson wrote: > We did a lot more debugging on the TC12 LINCtape controller. > > We saw a 500ns glitch in the LMU MOTION signal that corresponded to a short > slowdown in tape speed. We will investigate this next week. > > We entered the LINC instruction to check a

Re: PDP-12 Restoration at the RICM

We did a lot more debugging on the TC12 LINCtape controller. We saw a 500ns glitch in the LMU MOTION signal that corresponded to a short slowdown in tape speed. We will investigate this next week. We entered the LINC instruction to check a single block (0707) in the left switches and a block numb

Re: PDP-12 Restoration at the RICM

We found a shorted diode in one of the rectifiers in the +/-42VDC supply in the VR14 that was causing the main fuse to blow. The donor of the PDP-12 gave us a spare so that was an easy fix. We reinstalled the VR14 in the PDP-12 and ran the display diags. The VR14 display actually works! We found

Re: PDP-12 Restoration at the RICM

When we first powered up the PDP-12 the main fuse for the VR12 display blew. A replacement fuse did the same. We thought that the brown goo in the bottom of the chassis had leaked from the high-voltage power supply, and the high-voltage power supply is directly connected to the input, so that was t

RE: PDP-12 Restoration at the RICM

> > We reconnected the Variac to the input and with 10VAC the high-voltage > power supply had a 1000VDC output. We put 10x 500kOhm resistors in series > across the output and increased the Variac voltage. By measuring the > voltage across one resistor we could see that the output was more than > 1

RE: using new technology on old machines. Was: PDP-12 Restoration at the RICM

machines. Was: PDP-12 Restoration > at the RICM > > On 06/14/2015 12:41 PM, Simon Claessen wrote: > > as long as it is done in a way that it can be restored to its > > original, i have no problems in using newer technology in older > > machines. we have a alix sbc build into our

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

Not all EE's have the same education with regard to how semiconductors function. When I was in school I took a class in semiconductor physics - an entire semester on how the wee beasties function - more than most EEs. The prof., Henry Guckel, told an interesting story about an advanced IBM comput

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On 15 June 2015 at 22:55, Mark J. Blair wrote: > >> On Jun 15, 2015, at 13:46 , Pontus Pihlgren wrote: >> >> On Mon, Jun 15, 2015 at 04:55:57PM +, tony duell wrote: >>> >>> Unfortunately I believe you. Use at least a thousand times more components >>> than >>> you need to. >> >> Actually it'

Re: PDP-12 Restoration at the RICM

We spent a few more hours on the PDP-12 today... With the machine just powered on the stack 0/1 regulator output was 20.04V. With tune3 running in field 1 and testing field 0 the stack 0/1 regulator output was 19.93. No memory errors were reported. When the voltage was adjust up to 22.5 and down

Re: PDP-12 Restoration at the RICM

The LINK indicator light on the front panel of the PDP-12 failed two weeks ago. The indicator light bulb failed, briefly shorted, and destroyed the transistor that turns the indicator on. An new transistor and bulb, and all is well. We have been chasing a transient problem in the PDP-12 core memor

Re: OT: Steam Shovels [Was: Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM]

On Thu, Jun 18, 2015 at 08:25:46AM +0200, Pontus Pihlgren wrote: > On Wed, Jun 17, 2015 at 09:26:38PM +0200, Alexander Schreiber wrote: > > > > That has been done before for production purposes. I kid you not. > > I believe you. I found this on youtube, looks like the have some sort of > generat

OT: Steam Shovels [Was: Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM]

On Wed, Jun 17, 2015 at 09:26:38PM +0200, Alexander Schreiber wrote: > > That has been done before for production purposes. I kid you not. I believe you. I found this on youtube, looks like the have some sort of generator or boiler external to the shovel. Perhaps it's compressed air? https://ww

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On Mon, Jun 15, 2015 at 10:53:33PM +0200, Pontus Pihlgren wrote: > On Mon, Jun 15, 2015 at 04:53:01PM +, tony duell wrote: > > > > > I also think it is in the spirit of the computer - using what is available > > > to fix a problem at hand. I think the arduino was overkill when an attiny > > >

Re: Windows and devices - was Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> On Jun 17, 2015, at 10:50 , Toby Thain wrote: > Here's a cute gotcha I hit this week: > > - Have a running Windows 8.1 machine with PS/2 keyboard. > - Shut it down, start up with only USB keyboard. > - Shut down and boot again with PS/2 keyboard atached. > - Windows ignores it (although BIOS f

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

(I would change the subject line, but I am not sure how to do it in my ISP's web mail client) As far as I know XH558 will be permanently stationed at Finningley after this year's flying season is completed. The full details are here: http://www.vulcantothesky.org/, including dates of flypasts and

Windows and devices - was Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On 2015-06-16 1:14 AM, Mark J. Blair wrote: ... Maybe this isn't the best time or place for this particular rant, but in my opinion, Windows' implementation of USB is fundamentally broken. It's a mouse, you stupid computer! You shouldn't need to spend a minute or more installing a new device dri

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On Mon, Jun 15, 2015 at 10:14:18PM -0700, Mark J. Blair wrote: > > > On Jun 15, 2015, at 21:59, tony duell wrote: Even > > though there are at least 4 different USB connectors > > Ok, you got me there! When I was working for a GPS startup, I used mini-B on > everything I designed with USB (a

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On 17 June 2015 at 05:09, Huw Davies wrote: > Funny I was discussing just this pair of planes last night - I last saw them > fly in 1971 at RAF Shawbury. Of course they were both in active service then > and I remember watching the Lightning do a supersonic pass with much joy. > Off topic for a

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> On 16 Jun 2015, at 7:27 am, Robert Jarratt > wrote: > > And I saw an Avro Vulcan flying this weekend, this year is the last time > that will ever happen. Two weeks before that I watched a General Electric > Lightning blast down a runway that I was standing right next to (it wasn't > allowed t

RE: PDP-12 Restoration at the RICM

> > Date: Mon, 15 Jun 2015 19:42:42 -0400 > From: Michael Thompson > To: cctech > > The M452 creates a 220 Hz clock for the TTY transmitter and a 880 Hz clock > for the TTY receiver. > The M405 for the DP12-B serial port generated a clock that is 16x the baud > rate which is then divided by an M2

RE: PDP-12 Restoration at the RICM

> > The PDP-12 came to us with an M452 for the 110 baud TTY console and a > home-made adjustable baud rate module for the second serial port. The > adjustable baud rate generator was made by the original user of the system > in the early 80s, and is just a crystal, rotary switch and a Fairchild >

RE: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On Tue, 16 Jun 2015, tony duell wrote: Actually, IIRC a USB A male->female cable violates the spec... The spec forbids extending the cable further? Or should the spec forbid absolutely any cable, with absolutely any USB connector on either end?

RE: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> > Sounds to me like you are more of a victim than a perpetrator here. Isn't > > there some OSHA regulation against > > USB A to A cables? :) > well, you know, it's a different world these days. You go to these places > down dark alleys, surrounded by shady characters and you can buy them. O

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

Again, I wonder if the data retention time decreases as the number of bits per device increases. Intuitively it should. Mind you, any SD card is probably going to be more reliable than a real TU58 tape now :-) I think that paper tape, used outdoors on a rainy day, is likely to be more reliable

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On Tuesday (06/16/2015 at 07:43AM -0700), Mark J. Blair wrote: > > > On Jun 16, 2015, at 07:36, Chris Elmquist wrote: > > So, now you have to use a Type A to Type A cable to connect this box to > > your computer. > > > > That is just really, really messed up and I honestly tried to make it > > r

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> On Jun 16, 2015, at 07:36, Chris Elmquist wrote: > So, now you have to use a Type A to Type A cable to connect this box to > your computer. > > That is just really, really messed up and I honestly tried to make it > right but it was like pushing a rope. > > I hope my friends will visit me in

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On Tuesday (06/16/2015 at 07:24AM -0700), Mark J. Blair wrote: > > > On Jun 16, 2015, at 06:46, tony duell wrote: > > > > Again, I wonder if the data retention time decreases as the number of bits > > per device increases. Intuitively it should. Mind you, any SD card is > > probably > > going t

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On Monday (06/15/2015 at 10:14PM -0700), Mark J. Blair wrote: > > > On Jun 15, 2015, at 21:59, tony duell wrote: > > Even though there are at least 4 different USB connectors > > Ok, you got me there! When I was working for a GPS startup, I used mini-B on > everything I designed with USB (a

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

Choosing the larger card is, IMO, the right answer because you don't actually waste the space, you extend the life significantly because the wear leveling will spread your 256K across the entire flash region. The larger that region, the less often you re-write the same cells, thereby extending the

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> On Jun 16, 2015, at 06:46, tony duell wrote: > > Again, I wonder if the data retention time decreases as the number of bits > per device increases. Intuitively it should. Mind you, any SD card is probably > going to be more reliable than a real TU58 tape now :-) I think that paper tape, used

RE: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> > > > I am of course counting all the transistors inside that chip. > > Well, that was obvious. But it raises an interesting point, today you > can cram a whole computer in the footprint of the simplest DIP carrier. > For the same price point and same reliablity. Is it then overkill if you > cho

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On Tue, Jun 16, 2015 at 04:28:16AM +, tony duell wrote: > > I am of course counting all the transistors inside that chip. Well, that was obvious. But it raises an interesting point, today you can cram a whole computer in the footprint of the simplest DIP carrier. For the same price point an

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On Tue, Jun 16, 2015 at 04:32:23AM +, tony duell wrote: > > Oh come on. You yourself said you are here to learn. This module > is hardly complicatated. Well, you got me there :) /P

RE: PDP-12 Restoration at the RICM

> > Date: Mon, 15 Jun 2015 05:01:36 + > From: tony duell > Subject: RE: PDP-12 Restoration at the RICM (tony duell) > > > > Tony, thank you for your offer to supply replacement M452 Variable Clock > > modules for the console. We already have one jumpered for 1

RE: PDP-12 Restoration at the RICM

> > The M452 creates a 110 Hz clock for the TTY transmitter and a 880 Hz clock > for the TTY receiver. Does it? The prints I have show the 2 outputs with a factor of 4 (not 8) in frequency. > The M405 for the DP12-B serial port generated a clock that is 16x the baud > rate which is then divided

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> On Jun 15, 2015, at 21:59, tony duell wrote: > Even though there are at least 4 different USB connectors Ok, you got me there! When I was working for a GPS startup, I used mini-B on everything I designed with USB (always devices, never hosts, and no need for USB OTG). Then we got bought

RE: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> > In my opinion, the magic is inside the transistor. Once you bottle enough > magic to make a good transistor, the > rest is pretty straightforward. :) Err, yes... It is impossible to understand the transistor using classical physics People have made transistors at home, even made their

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> On Jun 15, 2015, at 21:28, tony duell wrote: > As am I. I've learnt a heck of a lot since I started (there is a common myth > that there is something magic about a processor. This hobby has taught > me to understand quite a few at the gate level). And the day I stop learning > is the day I am i

RE: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> > > > I am very worried that people would rather use a microcontroller than change > > a couple of passives. Can't anyone read a schematic and think > > Nope. I didn't know this hobby required a degree in electrical > engineering. Well it had better not. I don't have one > By your criteria

RE: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> > > > Unfortunately I believe you. Use at least a thousand times more components > > than > > you need to. > > Actually it's just two, a Teensy and a usb cable. (Sorry, I couldn't > resist). I am of course counting all the transistors inside that chip. > How do you suggest I learn? I believe

RE: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> > I am very worried that people would rather use a microcontroller than change > > a couple of passives. Can't anyone read a schematic and think > > The exact same argument could be made for somebody using an NE555 instead of > discrete transistors to blink an > LED, or discrete transistor

RE: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> > Why not do it properly first time? What is the rush in bringing up a > > classic computer? And for a test, > > use the TTL pulse generator you have on your bench. > > I don't have one. I have a lot of test equipment, but mostly for RF work. If > I needed to generate TTL pulses, I'd > proba

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> On Jun 15, 2015, at 14:27 , Robert Jarratt > wrote: > This particular thread has all the hallmarks of one that *could* descend > into a flame war. Thank you for avoiding that! I think we're doing ok. The same folks having a spirited debate in this thread are carrying on just fine together in

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> On Jun 15, 2015, at 14:56 , Dave G4UGM wrote: > > A friend of mine refused to buy modern SD Cards because there was no way he > was going to fill them. Trouble is that although smaller SD cards were > available they were way more expensive (being discontinued and therefore > rare and valuable)

RE: using new technology on old machines. Was: PDP-12 Restoration at the RICM

ing new technology on old machines. Was: PDP-12 Restoration > at the RICM > > > > On Jun 15, 2015, at 13:46 , Pontus Pihlgren > wrote: > > > > On Mon, Jun 15, 2015 at 04:55:57PM +, tony duell wrote: > >> > >> Unfortunately I believe you. U

RE: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> -Original Message- > From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Pontus > Pihlgren > Sent: 15 June 2015 22:06 > To: General Discussion: On-Topic and Off-Topic Posts > Subject: Re: using new technology on old machines. Was: PDP-12 Restoration at >

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On Mon, Jun 15, 2015 at 01:59:11PM -0700, Mark J. Blair wrote: > > Big. VERY big. :) > > And one more thing (until the next thing comes to mind): I consider > this to be an enjoyable and level-headed debate, just in case anybody > gets the mistaken impression that I'm trying to come down hard on

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> On Jun 15, 2015, at 13:53 , Pontus Pihlgren wrote: > No but I would put an electric heater in a steam engine if it meant > restoration would progress faster. As long as you don't damage the firebox installing your heater, what's the big deal? Making first steam is going to be a gradual and c

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> On Jun 15, 2015, at 13:46 , Pontus Pihlgren wrote: > > On Mon, Jun 15, 2015 at 04:55:57PM +, tony duell wrote: >> >> Unfortunately I believe you. Use at least a thousand times more components >> than >> you need to. > > Actually it's just two, a Teensy and a usb cable. (Sorry, I couldn'

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On Mon, Jun 15, 2015 at 04:53:01PM +, tony duell wrote: > > > I also think it is in the spirit of the computer - using what is available > > to fix a problem at hand. I think the arduino was overkill when an attiny > > (smaller, easier to hide) would probably serve just as well. > > Would you

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On Mon, Jun 15, 2015 at 07:15:14PM +, tony duell wrote: > > I am very worried that people would rather use a microcontroller than change > a couple of passives. Can't anyone read a schematic and think Nope. I didn't know this hobby required a degree in electrical engineering. By your cr

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> On Jun 15, 2015, at 11:54 , tony duell wrote: > Ah, 'there's not the time to do it properly, but there is the time to do it > again'. > > Why not do it properly first time? What is the rush in bringing up a classic > computer? Sorry for yet another reply, but I didn't think of this until ju

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On Mon, Jun 15, 2015 at 04:55:57PM +, tony duell wrote: > > Unfortunately I believe you. Use at least a thousand times more components > than > you need to. Actually it's just two, a Teensy and a usb cable. (Sorry, I couldn't resist). > > In general this worries me if you are restoring a

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> On Jun 15, 2015, at 12:15 , tony duell wrote: > > I am very worried that people would rather use a microcontroller than change > a couple of passives. Can't anyone read a schematic and think The exact same argument could be made for somebody using an NE555 instead of discrete transistors

RE: PDP-12 Restoration at the RICM (tony duell)

> Tony, thank you for your offer to supply replacement M452 Variable Clock > modules for the console. We already have one jumpered for 110 baud for the > Teletype. The other two M452 modules should be jumpered for 9600 baud and > 38400 baud. The second serial port uses a M405 Crystal Clock module

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> On Jun 15, 2015, at 11:54 , tony duell wrote: > Why not do it properly first time? What is the rush in bringing up a classic > computer? And for a test, > use the TTL pulse generator you have on your bench. I don't have one. I have a lot of test equipment, but mostly for RF work. If I needed

RE: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> We're talking about putting in a rather complex computer to generate a > baud rate. Are people really that handicapped when it comes to building > hardware nowadays? Are people aware how easy baud generators are? I've jsut turned up the M452 schematic. Has anyone else looked at it? It's a RC

RE: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> > > > Would you put plastic handles on a piecc of antique furniture? Would you > > make the seatboard for an antique longcase clock from MDF? > > Both are easily reversable, BTW. > > Sure! Temporarily and reversibly, of course, and I'd hope to replace them > with proper stuff when possible. But

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> On Jun 15, 2015, at 09:53 , tony duell wrote: > > >> I also think it is in the spirit of the computer - using what is available >> to fix a problem at hand. I think the arduino was overkill when an attiny >> (smaller, easier to hide) would probably serve just as well. > > Would you put plast

Re: FPGA tricks - Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On 6/15/2015 11:33 AM, Paul Koning wrote: On Jun 15, 2015, at 1:28 PM, ben wrote: On 6/15/2015 10:57 AM, Dave G4UGM wrote: But alas the software does *not* support the older chips. How old is old? I managed to get a copy of ISE10.1 downloaded, installed and running without phoning, ringing

Re: FPGA tricks - Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> On Jun 15, 2015, at 1:28 PM, ben wrote: > > On 6/15/2015 10:57 AM, Dave G4UGM wrote: >> But alas the software does *not* support the older chips. >> >> How old is old? I managed to get a copy of ISE10.1 downloaded, >> installed and running without phoning, ringing or otherwise jumping >> thro

Re: FPGA tricks - Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On 6/15/2015 10:57 AM, Dave G4UGM wrote: But alas the software does *not* support the older chips. How old is old? I managed to get a copy of ISE10.1 downloaded, installed and running without phoning, ringing or otherwise jumping through hoops. That supports the Spartan 2 which has been obsolete

Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On 06/14/2015 12:41 PM, Simon Claessen wrote: as long as it is done in a way that it can be restored to its original, i have no problems in using newer technology in older machines. we have a alix sbc build into our tek 4002a for demonstrational purpouses, all done without damaging or altering th

RE: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> > We're talking about putting in a rather complex computer to generate > > a baud rate. Are people really that handicapped when it comes to > > building hardware nowadays? > > Speaking for myself, yes. Unfortunately I believe you. Use at least a thousand times more components than you need to.

RE: FPGA tricks - Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> -Original Message- > From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of ben > Sent: 15 June 2015 17:18 > To: cctalk@classiccmp.org > Subject: Re: FPGA tricks - Re: using new technology on old machines. Was: > PDP-12 Restoration at the RICM > > On

RE: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> I also think it is in the spirit of the computer - using what is available > to fix a problem at hand. I think the arduino was overkill when an attiny > (smaller, easier to hide) would probably serve just as well. Would you put plastic handles on a piecc of antique furniture? Would you make th

Re: FPGA tricks - Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

> On Jun 15, 2015, at 09:18, ben wrote: > But alas the software does *not* support the older chips. > You want to make a mod 5 years down the road, sorry we do not > support that model any more. TTL needs to be stock piled > now for the next +50 years. Good point. Just as TTL needs to be stockp

Re: FPGA tricks - Re: using new technology on old machines. Was: PDP-12 Restoration at the RICM

On 6/15/2015 9:08 AM, Toby Thain wrote: On 2015-06-15 9:35 AM, Dave G4UGM wrote: I don't think it is over kill. If you want over kill try this:- https://www.youtube.com/watch?v=ALXax3Gydl8 and FPGA implementation of the Baby or SSEM which had 32x32 bits of RAM. The implementation uses around

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