Image Map Image Map
Tab Content
  • Mike_Z's Avatar
    Yesterday, 04:56 PM
    Mike, the typing machine/keyboard and the reader/punch are in parallel. So when one works they both can. There is a power switch to stop the punch...
    24 replies | 587 view(s)
  • Mike_Z's Avatar
    Yesterday, 11:55 AM
    I didn't have an opportunity to look at this over the weekend. Saturday it snowed, spent time shoveling, warning up and shoveling more. Sunday we...
    24 replies | 587 view(s)
  • Mike_Z's Avatar
    January 18th, 2019, 04:45 PM
    Here is the header block of the ASR33.BN file I found on my disks. *0 -1 DEVICE AS33; DEVICE TTY;0;1; ZBLOCK 2 TTYVERSION="A&77
    24 replies | 587 view(s)
  • Mike_Z's Avatar
    January 18th, 2019, 04:28 PM
    Nothing was printed. In fact looking at what entry point address was loaded from the fetch, I see that the ASR33 device handler code has a return...
    24 replies | 587 view(s)
  • Mike_Z's Avatar
    January 18th, 2019, 11:10 AM
    Made some progress today. Wrote a device handler call and the first attempt of using it failed. Found a few code mistakes and after the changes the...
    24 replies | 587 view(s)
  • Mike_Z's Avatar
    January 17th, 2019, 07:27 AM
    Well..... after some horsing around I think the TTY device handler loaded. Thinking about it, I wanted to be sure that I had the correct device...
    24 replies | 587 view(s)
  • Mike_Z's Avatar
    January 16th, 2019, 12:34 PM
    Well..... this is what I tried (and it didn't work, at least in my estimation). 0200 7200 CLA 0201 6201 CDF 0 0202 6212 CIF 10 0203 ...
    24 replies | 587 view(s)
  • Mike_Z's Avatar
    January 16th, 2019, 12:08 PM
    I found information regarding the address of (USR, but I'm confused. Page 2-1 states the USR is either 7700 or 0200. Then on page 2-2 states, the USR...
    24 replies | 587 view(s)
  • Mike_Z's Avatar
    January 16th, 2019, 10:39 AM
    Am I correct in thinking that OS/8 loads the device handlers into memory field zero. Then the Fetch call for the TTY device handler loads the handler...
    24 replies | 587 view(s)
  • Mike_Z's Avatar
    January 16th, 2019, 10:08 AM
    I've been studying the I/O routines listed in appendix F of the OS/8 Software Support Manual. There is ICHAR, OCHAR, IOPEN, OOPEN, and OCLOSE. Am I...
    24 replies | 587 view(s)
  • Mike_Z's Avatar
    January 15th, 2019, 03:36 PM
    Looks like it does work. I missed the fact that the data is stored as 6 bit ASCII 14 = L 05 = E 01 = A 04 = D 05 = E 22 = R 0000 is the...
    24 replies | 587 view(s)
  • Mike_Z's Avatar
    January 15th, 2019, 03:19 PM
    I found more information in the OS/8 language reference manual. The introduction to programming doesn't talk about this. I'll read this and try some...
    24 replies | 587 view(s)
  • Mike_Z's Avatar
    January 15th, 2019, 03:10 PM
    Mike, this looks like what I asked for, but I'm not sure this will work with PAL8. The code in the example on page F-4 has pseudo op codes that I...
    24 replies | 587 view(s)
  • Mike_Z's Avatar
    January 15th, 2019, 11:14 AM
    I've taken up learning more about OS/8 and it's programs. Currently, I'm working with PAL8. I was wondering whether or not OS/8 has any callable...
    24 replies | 587 view(s)
  • Mike_Z's Avatar
    January 6th, 2019, 09:02 AM
    Mike_Z replied to a thread Power Supply grounding in DEC
    I can't find the PDP-1 picture and maybe it wasn't a Friden, but I did find this on Wiki, regarding PDP-1. "Offline devices are typically Friden...
    39 replies | 1318 view(s)
  • Mike_Z's Avatar
    January 6th, 2019, 08:15 AM
    Mike_Z replied to a thread Power Supply grounding in DEC
    Well..... I pretty much have the Friden interface with the CP/M machine. What puzzles me is that the Friden keyboard is permanently attached to the...
    39 replies | 1318 view(s)
  • Mike_Z's Avatar
    January 5th, 2019, 07:04 AM
    Mike_Z replied to a thread Power Supply grounding in DEC
    That is interesting. I have noticed this also. I have a $20 digital multi meter which acts just like you say. My Simpson 260 seems to work better and...
    39 replies | 1318 view(s)
  • Mike_Z's Avatar
    January 4th, 2019, 03:38 PM
    Mike_Z replied to a thread Power Supply grounding in DEC
    OK, I didn't see that part of box.com. The Friden is a machine that was designed to communicate with other Friden machines or to make paper tapes...
    39 replies | 1318 view(s)
  • Mike_Z's Avatar
    January 4th, 2019, 01:44 PM
    Mike_Z replied to a thread Power Supply grounding in DEC
    I do this in real time also, sometimes when I talk, i think I've said something and I didn't, or assume those who I'm talking with understand and see...
    39 replies | 1318 view(s)
  • Mike_Z's Avatar
    January 4th, 2019, 01:33 PM
    Mike_Z replied to a thread Power Supply grounding in DEC
    Suppose I should have been clearer. I placed the filter cap on the Firden Power supply, right after the rect bridge. It did raise the overall supply...
    39 replies | 1318 view(s)
  • Mike_Z's Avatar
    January 4th, 2019, 12:59 PM
    Mike_Z replied to a thread Power Supply grounding in DEC
    How is this? https://filebin.net/f4nyxnwrz90771cg/PrintInterface.pdf?t=4ply0l20 Yes the referenced ground is not the Friden frame. AND I added...
    39 replies | 1318 view(s)
  • Mike_Z's Avatar
    January 4th, 2019, 12:49 PM
    Mike_Z replied to a thread Power Supply grounding in DEC
    Box.com wants $5/month. I'll look for a free one. Mike
    39 replies | 1318 view(s)
  • Mike_Z's Avatar
    January 4th, 2019, 11:35 AM
    Mike_Z replied to a thread Power Supply grounding in DEC
    Here is the output diagram. I only have a hand drawn input circuit, so far. The way this works is the translator magnets are selected via port 154...
    39 replies | 1318 view(s)
  • Mike_Z's Avatar
    January 4th, 2019, 07:52 AM
    Mike_Z replied to a thread Power Supply grounding in DEC
    I do use opto isolaters between the Friden and the other machines. I have the grounds of each isolated, Yet the 60 cycle noise still gets in. ...
    39 replies | 1318 view(s)
  • Mike_Z's Avatar
    January 3rd, 2019, 04:47 PM
    Mike_Z replied to a thread Power Supply grounding in DEC
    My Friden is a Flexowriter SFD-V from the late 1950's. I think the -V means it has the edge card reader attachment. Not sure what a 7000 series is....
    39 replies | 1318 view(s)
  • Mike_Z's Avatar
    January 3rd, 2019, 01:34 PM
    Mike_Z replied to a thread Power Supply grounding in DEC
    The Friden power supply is rather odd. There is no primary transformer. The 120 AC is applied directly to a bridge rectifier through a 30 ohm...
    39 replies | 1318 view(s)
  • Mike_Z's Avatar
    January 3rd, 2019, 09:50 AM
    Mike_Z started a thread Power Supply grounding in DEC
    I have been working on an interface between my CP/M machine and Friden SFD-V. There is some 60 cycle, AC noise on the power supply that is...
    39 replies | 1318 view(s)
  • Mike_Z's Avatar
    December 31st, 2018, 07:25 AM
    I have not noticed this, so I tried it a dozen or so times with no problem. I use older stuff maybe that is the case. Most of my 'modern' computers...
    17 replies | 787 view(s)
  • Mike_Z's Avatar
    December 30th, 2018, 08:42 AM
    Well..... I have froze and thawed the problematic wire wrap wire a half dozen times. I think it has helped. The insulation does come off better and I...
    16 replies | 965 view(s)
  • Mike_Z's Avatar
    December 29th, 2018, 08:05 AM
    Mike_Z replied to a thread PPI Programmed buffers in S-100
    Today, I added the real ~WRITE signal from the CPU to the logic analyzer traces. What do you know, the ~WR is one clock cycler later. In this picture...
    4 replies | 358 view(s)
More Activity
About Mike_Z

Basic Information

About Mike_Z
Biography:
Retired Old Steam Power Plant Engineer
Location:
Near Milwaukee Wisconsin
Interests:
Old stuff, computers, cars, furniture, houses
Occupation:
Retired

Statistics


Total Posts
Total Posts
1,109
Posts Per Day
0.59
General Information
Last Activity
Yesterday 04:56 PM
Join Date
December 1st, 2013
Referrals
0