test-drb November 2019

test-drb@ccmp.vtda.org

147 participants
137 discussions

by bill.gunshannon＠hotmail.com

It's not really classic (although it does try to pretend to be :-) but does anyone here do anything with the P118 SBC? I am trying to get 8" disks running on it but I am seeing some rather strange behavior. bill

5 years, 1 month

Intel 8272 based floppy controller & Missing Address Mark

by dkgrizzly＠thewaffleiron.net

Hi friends, In the continuing saga of building a CP/M system with Pro-Log cards housed in a Heathkit dual 8? floppy drive cabinet I recently acquired a Pro-Log 7387 floppy disk controller card w/ manuals. The 8272 chip on the card was fried (either before I got it, or by me doing something stupid early on once I had acquired it), and so I replaced the chip with another pulled from a 8-bit ISA floppy controller. Now I am getting some more reasonable replies out of the card. Now I'm stuck with "Missing Address Mark" errors, no matter if I'm using a real 8" floppy drive (8MHz FDC clock, appropriate settings in all the software) or a GoTek floppy emulator (4MHz FDC clock, 720KB settings on the GoTek & Floppy Disk Utility). I can see the read data & read window lines working as I'd expect, so I'm fairly confident that the read data separator and related logic is OK (I even replaced the 74ls74 read data separator with no effect). What am I missing that would cause a 8272 to always return Missing Address Mark? I'm using RomWBW, with the included FDU utility patched to talk to the FDC at the correct addresses, and from the traces I've captured it appears that side of things is working correct. I'm hoping someone out there has experience troubleshooting floppy controllers?and can give me some pointers. -David ------ Trace with GoTek running FlashFloppy and emulating a 720KB drive follows ------- RetroBrew HBIOS v2.9.1-pre.5, 2019-11-23 PROLOG Z80 @ 3.686MHz 0 MEM W/S, 1 I/O W/S, INT MODE 1 512KB ROM, 2048KB RAM SIO0: IO=0xF5 SIO MODE=9600,8,N,1 SIO1: IO=0xF7 SIO MODE=9600,8,N,1 MD: UNITS=2 ROMDISK=384KB RAMDISK=1920KB FD: IO=0xC4 UNITS=2 Unit Device Type Capacity/Mode ---------- ---------- ---------------- -------------------- Disk 0 MD1: RAM Disk 1920KB,LBA Disk 1 MD0: ROM Disk 384KB,LBA Disk 2 FD0: Floppy Disk 3.5",DS/DD,CHS Disk 3 FD1: Floppy Disk 3.5",DS/DD,CHS Serial 0 SIO0: RS-232 9600,8,N,1 Serial 1 SIO1: RS-232 9600,8,N,1 PROLOG Z80 Boot Loader Boot: (C)PM, (Z)System, (M)onitor, (L)ist disks, or Disk Unit # ===> BOOT CPM FROM ROM CBIOS v2.9.1-pre.5 [WBW] Formatting RAMDISK... Configuring Drives... A:=MD1:0 B:=MD0:0 C:=FD0:0 D:=FD1:0 3623 Disk Buffer Bytes Free CP/M-80 v2.2, 54.0K TPA B> FDU Floppy Disk Utility (FDU) v5.2, 08-Jan-2018 [HBIOS] Copyright (C) 2017, Wayne Warthen, GNU GPL v3 SELECT FLOPPY DISK CONTROLLER: (0) Exit (1) Disk IO ECB Board (2) Disk IO 3 ECB Board (3) Zeta SBC Onboard FDC (4) Zeta 2 SBC Onboard FDC (5) Dual IDE ECB Board (6) N8 Onboard FDC (7) RC2014 SMC (SMB) (8) ProLog 7387 === OPTION ===> PL ===== PL ==============<< FDU MAIN MENU >>====================== (S)ETUP: UNIT=00 MEDIA=720KB MODE=POLL TRACE=00 ---------------------------------------------------------------- (R)EAD (W)RITE (F)ORMAT (V)ERIFY (I)NIT BUFFER (D)UMP BUFFER FDC (C)MDS E(X)IT === OPTION ===> FORMAT (T)RACK, (D)ISK ===> DISK ENTER INTERLEAVE [01-09] (02): RESET DRIVE... PROGRESS: TRACK=4F HEAD=01 SECTOR=01 ===== PL ==============<< FDU MAIN MENU >>====================== (S)ETUP: UNIT=00 MEDIA=720KB MODE=POLL TRACE=00 ---------------------------------------------------------------- (R)EAD (W)RITE (F)ORMAT (V)ERIFY (I)NIT BUFFER (D)UMP BUFFER FDC (C)MDS E(X)IT === OPTION ===> READ (S)ECTOR, (T)RACK, (D)ISK, (R)ANDOM ===> TRACK ENTER TRACK [00-4F] (00): ENTER HEAD [00-01] (00): PROGRESS: TRACK=00 HEAD=00 SECTOR=01 READ: 46 00 00 00 01 02 09 2A FF --> 40 01 00 00 00 01 02 [MISSING ADDRESS MARK] CONTINUE? (A)BORT, (R)ETRY, (I)GNORE ===>

5 years, 1 month

IBM SP/SP2 9076

by kevin.bowling＠kev009.com

Anyone have one of these collecting dust? Regards, Kevin

5 years, 1 month

PDP - 8 Front panels

by rodsmallwood52＠btinternet.com

Hello Everybody ?After a two year pause due to my wife having been ill but now fully recovered I am back to starting making pdp-8 front panels again I have some stock: pdp-8/e (type A - vertical selector switch start mark) pdp-8/e (type B -? selector? switch start to left of vertical) pdp-8/f panels As pdp8/f but no /f marking. - doing a /m overprint for it pdp8/i I am looking for scrap pdp/8 panels (might trade for a new one), hi res front (and back) dead center pictures (panel on its own) and accurate dimensions (including holes) of any pdp-8 panel to aid me in offering the complete range. PDP-11 ?? Not at this time but maybe later I am busy at the moment with artwork redrawing. The UK winter is not kind to making screens. Even in good warm weather the exposed and washed out screen in its frame takes 24 hours to dry. Then after printing each layer (up to five per panel) takes 24hrs to dry before another layer can be added. Authentic panels produced the exact way they were in the '60s and '70s ain't going to be quick or cheap. But the result is sure worth it. Rod 'Panelman' Smallwood (Digital Equipment Corporation 1975 - 1985) --

5 years, 1 month

TSS/8 on RK05

by mosst＠SDF.ORG

That's great Josh, I look forward to seeing it in action when I'm next at LCM+L! I had been thinking of doing something similar myself, as I also have an 8/e and RK05, but no RF08. Thanks for making the code available :) Regards, -Tom mosst at sdf.lonestar.org SDF Public Access UNIX System - http://sdf.lonestar.org

5 years, 1 month

Scanning docs for bitsavers

by jnc＠mercury.lcs.mit.edu

> From: Jay Jaeger > CCITT Group 4 lossless compression That's very good indeed. I scan text pages in B+W at slightly less resolution (engineering prints I do higher, they need it), but compressed they turn out to be ~50KB per page, or less - for long documents (e.g. the DOS-11 System Programmer's Manual), that produces a reasonably-sized file. > The software I have been using i[s] Irfanview. That's what I use too; it has tons of useful features, including being able to drive my single-sided page-feed scanner and being able to number the even-sided pages correctly. The one I use for this is the 'batch mode'; I can do the entire document into CCITT 4 in one operation. Noel

5 years, 1 month

TSS/8 on RK05

by derschjo＠gmail.com

Hi all -- We've wanted to run TSS/8 on one of our PDP-8 systems at LCM+L for a long time now, and while we contemplated either (a) restoring our RF08 or (b) building an RF08 emulator, I decided it might be fun to investigate a third option: (c) modify TSS/8 to run off hardware we already have running, namely an RK05 drive. And it /was/ fun! And seems to have been successful, as we now have TSS/8 running on our PDP-8/e. Performance is acceptable, and it seems to be stable so far. The changes I made are here: https://github.com/livingcomputermuseum/cpus-pdp8 This is a fork of a codebase that Brad Parker put together a number of years back in which he did some serious work to get TSS/8 to build (amongst other things). I made use of this effort, which saved a lot of time and made building/testing my changes quite straightforward. I also modified the disk image: It's extended to 1MW (the maximum possible without modifying the filesystem code) and I ported a couple of extra programs to TSS/8 (CHEKMO and LISP). I figured some people here might also be able to take advantage of being able to run TSS/8 from RK05. I know RK8E's are pretty rare, but I'm also guessing more people have them than have working fixed-head disks :). If you do give it a try, let me know if you run into any issues or if you have any feature requests. Thanks, Josh

5 years, 1 month

VisiCorp VISI ON

by curt＠atarimuseum.com

Does anyone have original manuals/Disks for VISI ON? I?m looking for an original set and any of the VISI ON specific program packages.

5 years, 1 month

RL02 disk crashes and taking them apart

by cz＠alembic.crystel.com

One of the RL02 packs I have did not look happy upon inspection, so I opened it up. Note that it's a little more complicated to take these packs apart than simply pushing a small rod through the holes in the back of the pack handle: You have to take apart the whole handle mechanism to get to the pins holding the pack to the carriage in order to get the pack off. I'll post some pics of all that eventually. Meantime, pictures of the disk. As you can see the top platter of the disk has a number of concentric rings and a hard crash ring. My guess is this thing was loaded in a bad RL02 that promptly trashed it. Oh well, one for the record books.... Pics at: https://i.imgur.com/phdLWUF.jpg Close up of the damage https://i.imgur.com/yQnt8BJ.jpg Overall shot of the disk Never dull. C

5 years, 1 month

The information age

by dkelvey＠hotmail.com

It is such a shame that in the "information age", we have lost so much of the information. It doesn't help when we have people like Jobs that like to write their own version. It is even worse when companies think it is a law suite risk to keep information more than a year. It is all lost. "The information lost age" Dwight

5 years, 1 month

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test-drb November 2019