test-drb

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101090 discussions

by snhirsch＠gmail.com

Anyone on the list have experience installing A/UX on a 68k Mac? I'm running into some very odd issue trying to bring up my Centris 610. The Centris shipped with a 68LC040 processor and I've upgraded to a "full" RC68040 CPU, since that's a requirement for A/UX. The CD-ROM drive is one of the units known to be compatible with A/UX. The FAQ claims that the installer understands third-party hard disks (unlike the MacOS installer) so I'm trying to use (variously) an older IBM Deskstar 850MB and/or Fujitsu 500MB SCSI drive for the install target. Here's the odd part: With the original Apple-branded OEM Quantum drive (which I do not want to overwrite) on the SCSI bus the installer recognizes the CD-ROM and is willing to begin the process. However, with any of the third-party hard drives in the system it is unable to recognize _anything_ on the SCSI bus - doesn't see the hard disk or the CD-ROM. I've checked and double-checked the jumpering on the hard disk and it's not conflicting with the CD-ROM. Both the IBM and Fujitsu are fairly run-of-the-mill 50-pin SCSI units. I've never had issues in the past with non-Apple drives hanging the bus or preventing access to other devices, so this one's really a head-scratcher. Any ideas what might be throwing the SCSI subsystem for a loop? Steve --

15 years, 5 months

Disc drive READY output -- any standards?

by CCTECH＠beyondthepale.ie

> >> seems that instead of requiring a particular time between step pulses, >> these drives allow the controller to step as fast as it likes and they > >What happens with one of these drives is you slow the steppign rate (at >the cotnroller) right down, say to 20ms steps? Does it still sometimes >kil the index pulse? > I tested at the slowest stepping rate available on an unmodified BBC model B (which I think is 24ms) and it still failed occasionally. I suspect that it can fail no matter how slow the stepping rate is. > >Is this behavious properly documented anywhere? I guess that the days of >getting OEM and service manuals for such drives are long gone :-( > Pete Turnbull tells me that the TEAC data sheet for the FD-235HF series mentions it. He also has a write-up on the issue here: http://www.dunnington.u-net.com/public/BBC/index_and_READY.html Regards, Peter Coghlan.

15 years, 5 months

preparing an order for more S-100 boards

by lynchaj＠yahoo.com

Hi! I am preparing to order some additional S-100 board PCBs. At the moment, the most requested boards on the waiting list are below S-100 buffered prototyping board (12 waiting) S-100 4MB SRAM (11 waiting) S-100 EPROM (9 waiting) There needs about 20-25 firm builders on the waiting list to make a PCB manufacturing order feasible. I cannot afford a lot of leftover PCBs so it is important that most of these boards have a home before I will place an order. If you would like to get some S-100 PCBs based on the projects we have done already please contact me at LYNCHAJ at YAHOO.COM <mailto:LYNCHAJ at YAHOO.COM?subject=S-100> and I will add you to the waiting list. Please do not sign up if you are uncertain or unwilling to follow through with getting a PCB. Your word of honor is sufficient to me that you will follow through for PCBs on the waiting list. I still have a small number of S-100 parallel ASCII keyboard boards and S-100 PIC/RTC boards. In particular the S-100 PIC/RTC boards will be very important for the upcoming S-100 8086 CPU board John and I are working on. Thanks and have a nice day! Andrew Lynch PS a complete list of completed S-100 boards below. If you are interested in any of these boards please let me know however the number of builders on the waiting list probably means another board order is some time away. Regular Prototyping board Buffered Prototyping board 8 Slot Backplane IDE Parallel ASCII Keyboard converter 4MB SRAM System Monitor Board Bus Extender EPROM IO PIC/RTC Z80 CPU these are in work but not complete yet: Console IO ZFDC 68K CPU 8086 CPU

15 years, 5 months

FS: Apple II prototyping board

by charlesmorris800＠centurytel.net

FS: one unused "Suntronics" wire-wrap prototyping board for Apple II, complete with edge connector. No longer have the IIe ;) http://s1181.photobucket.com/albums/x426/DrCharlesMorris/?action=view&curre… $10, includes postage in US. thanks -Charles

15 years, 5 months

HP-UX .WAD file format?

by glen.slick＠gmail.com

Anyone here know anything about the .WAD file format in the context of HP-UX 9.0x, or more specifically in the context of an HP 16505A which is logic analyzer application running on top of HP-UX 9.0x on an HP 712/60? I have a set of MS-DOS FAT12 floppy disk images which each contain an UPDATE.WAD and an INFO.WAD file pair. I believe these must be compressed file archives. From looking at hex dumps of the files there are no obvious plain text strings. I would like to be able to view the archive contents and extract whatever files they might contain. Sample hex dumps below. These sample file pairs start with a common 15-byte file header: UPDATE.WAD (file size 320-bytes) 0000:0000 1f9d 9030 6e04 1c08-a320 8c18 060b ca80 ...0n...? ....?. 0000:0010 4123 e08d 1a0c 0fde-40d8 30c6 c484 3016 A#?....?(a)?0??.0. 0000:0020 6284 61a3 c68d 1920-1bda c038 03e2 c684 b.a??.. .??8.??. 0000:0030 75e6 c879 3107 8e9c-3763 d694 a133 e745 u??y1...7c?.?3?E 0000:0040 1937 765e 9849 c3a6-cc99 9775 e0cc 0130 .7v^.I???..u??.0 0000:0050 50a0 c084 0813 ce88-78e3 e149 a524 4f76 P??...?.x??I?$Ov 0000:0060 fc18 9223 4619 1a9f-c248 b9b2 e5cb 9833 ?..#F...?H????.3 0000:0070 6bde b443 d428 4183-490d 366c d8d4 a4d6 k??C?(A.I.6l???? INFO.WAD (file size 12043 bytes) 0000:0000 1f9d 9030 6e04 1c08-a320 8c18 060b ca40 ...0n...? ....?@ 0000:0010 18f0 8640 1a07 6f20-8418 4362 c283 170b .?. at ..o ..Cb?... 0000:0020 daa8 7163 8647 8836-6624 9401 31a3 8d18 ??qc.G.6f$..1?.. 0000:0030 366c 2081 82b2 068c-1a5f c690 f912 e30b 6l ..?..._?.?.?. 0000:0040 4417 65e4 c801 3022-c40b 3169 dcbc 5833 D.e??.0"?.1i??X3 0000:0050 078d 8211 0a8e 8250-0a62 65cb 9731 67c6 .......P.be?.1g? 0000:0060 8008 22e8 1c3a 61d8-b001 9153 ce1b 3920 .."?.:a??..S?.9 0000:0070 e68c 9193 060e 9da3-4947 a85d cbb6 ad5a ?......?IG?]???Z

15 years, 5 months

Teletype Tales Part 3

by tshoppa＠wmata.com

? There are no Teletypes that use Baudot code. They use a US variant of ? the ITA2 five-level code. ? Baudot code was only used until about 1901. Murray code was used until ? the 1930s. Everything after that used ITA2. That's a little like saying nobody actually uses ASCII since 1968, we're all really Using ANSI_X3.4-1968 or later. Technically true but not common usage. Everyone in the past half century has called a Model 28 TTY a Baudot Teletype when They had to distinguish it from any other type. (Baudot is still the default for Several applications so you don't even have to say it's Baudot.) I suppose classiccmp naturally attracts folks who care about such things (witness The thread I started over a few years ago when I noted that bitsavers had surpassed 100 GBytes and everyone informed me that no, a Gbyte was 1073741824 bytes so I was wrong.) Tim.

15 years, 5 months

When was the MicroVAX 3100 Model 95 Introduced?

by robert.jarratt＠ntlworld.com

I have found two conflicting sources for when this machine was introduced. According to Wikipedia (http://en.wikipedia.org/wiki/MicroVAX) it was April 1994. The source of this information appears to be this article: http://www.cbronline.com/archive/?SearchTerms=MicroVAX+3100+95 However, the following HP article http://h71000.www7.hp.com/openvms/20th/vmsbook.pdf on p60 (bottom right) suggests it is September 1992. Both sources would appear to be pretty reliable, but they can't both be right. Does anyone have any suggestion how I might determine which is the more accurate? Regards Rob

15 years, 5 months

Disc drive READY output -- any standards?

by classiccmp＠philpem.me.uk

Hi guys, Is there a defined standard as to when the READY output on a Shugart-type disc drive should go active? I'm (slowly!) working through the rebuild of one of the Amstrad drives (an EME231 I know to have working mechanical components, potentially good heads, and a fried control board), and I'm stuck on deciding how to deal with the READY output. My initial thought was to hold it inactive until a few INDEX pulses have passed, and the motor speed was within 5% of 'ideal' speed. The plan was to use a 32kHz oscillator and a 4040 counter to get a several-Hz signal, then rig up some logic to check that the disc speed was OK, and after a few valid index cycles enable the drive. Then I started wondering... am I over-engineering this? Would waiting for a couple of full disc rotations be enough to reliably generate a READY signal? Irony is that the read-amp will probably be the easiest part of the whole system... I've got a Motorola appnote which basically says "if you're using a data rate of X and a rotation speed of Y, these parameters will work" -- X and Y being the two parameters the Amstrad drive uses... That just leaves the write amp and erase logic to design (and maybe a 'write lockout' jumper). Thanks, -- Phil. classiccmp at philpem.me.uk http://www.philpem.me.uk/

15 years, 5 months

Character set pedanticness (was Re: Teletype)

by tshoppa＠wmata.com

Eric wrote: >>> There are no Teletypes that use Baudot code. They use a US variant of >>> the ITA2 five-level code. >>> Baudot code was only used until about 1901. Murray code was used until >>> the 1930s. Everything after that used ITA2. Tim wrote: >> That's a little like saying nobody actually uses ASCII since 1968, we're all really >> Using ANSI_X3.4-1968 or later. Technically true but not common usage. Eric wrote: > No, it's not much like that at all. Baudot code used significantly > different character encodings than ITA2, such that a Baudot device and > an ITA2 device will not interoperate in any meaningful fashion. > ASCII-63, ASCII-67, ASCII-68, and ANSI X3.4 have only minor variations > and will generally interoperate reasonably well. I'm not disagreeing that the academically correct term is ITA #2. (Interestingly most web page hits today call it "ITA 2" or "ITA2" but the 70's and earlier books call it "ITA #2" when they are being pedantic.) I'm just saying that in its Heyday, if you had to distinguish a 5-level TTY from a 7-level TTY, the working terms were Baudot and ASCII. Although technically incorrect. Sort of like when I know the people who used and maintained what they called a 11/74, and then I see folks here telling me that no, it's really A 11/70MP :-). Yeah, in a certain aspect that may be what the paperwork called it. But really everybody called it the 11/74. When I'm told that the academically correct word for something, is different than what everyone actually called it at the time, and I see Wikipedia etc. going for academically correct rather than "actual working term", it sometimes feels like history that I lived is being redefined underneath me by some sort of pedantic streak. Another recent example of a different character set being redefined underneath Me: On Wikipedia, the morse code for -...- is defined as "double dash" with a Possible keyboard equivalent of "equals sign", something I never heard till recently. I called it "BT" with a bar Over top for most of half a century now. I don't doubt that some CCITT standard Called it double dash in the past, just that me and the guys I know who use Morse every day, never called it that. This isn't new to me. I remember getting involved in altmode vs escape key arguments In the distant past. I always called it altmode, what right does anyone else Have to call it escape? :-))))). Big smileys, because I discovered that three Different ASCII codes (0174, 0175 and 033) were being used and I didn't know until Much much later. Tim.

15 years, 5 months

Disc drive READY output -- any standards?

by CCTECH＠beyondthepale.ie

> >My initial thought was to hold it inactive until a few INDEX pulses have >passed, and the motor speed was within 5% of 'ideal' speed. The plan was >to use a 32kHz oscillator and a 4040 counter to get a several-Hz signal, >then rig up some logic to check that the disc speed was OK, and after a >few valid index cycles enable the drive. > The BBC Micro internally generates the ready signal for the 8271 controller >from index, drive select and the 8MHz clock using a 74LS393, 4020 and 4013. I figured out how the circuit works once and my head still hurts. As far as I remember, it works like your description above and if an index pulse is a few percent later than expected, it deasserts ready. This was designed for 5.25in floppies and worked fine with early 3.5in drives. However a problem arose with more recent 3.5in drives. It seems that instead of requiring a particular time between step pulses, these drives allow the controller to step as fast as it likes and they signal the controller that the heads have not yet reached the required location by suppressing index until they do. The circuitry in the BBC notices the lack of index and drops the ready signal to the 8271 resulting in a "drive not ready" error when stepping by more than a couple of tracks (er, I mean cylinders) when using one of these drives. It seems the lessons are firstly that the designers of the BBC micro did not reckon they could rely on getting a good ready signal from the drive and secondly, no matter how you try to be clever, something will later come along to mess up your cunning plan. Regards, Peter Coghlan.

15 years, 5 months

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