Hello, all:
While in the process of examining my old P-E and R-E magazines, I came
across an ad for MITS from mid-1974. The ad was for a 4-channel digital
handheld memory scope (model MS416) for $189. It seems to be a simple
digital logic analyzer.
Does any one have info on this? If anyone's interested, I'll post the
picture.
Rich Cini/WUGNET <nospam_rcini(a)msn.com>
- ClubWin/CW7
- MCP Windows 95/Windows Networking
- Preserver of "classic" computers
<<<< ========== reply separator ========== >>>>>
Huw Davies <H.Davies(a)latrobe.edu.au> wrote:
>One question, what's the difference between the AB and CD slots in the
>backplane?
On *some* backplanes, there is no difference. A dual-high board could
be plugged into the CD side just was successfully as in the AB side.
In other backplanes, the AB side is the Qbus side, and the CD side is
set to connect adjacent boards so that they can communicate (such as
the VSV11, the RLV11, and the 11/83 and its PMI memory).
In yet other backplanes, you find that it is Qbus in the AB slots and
CD bus in the CD slots for part of the backplane (BA23 = three slots,
BA123 = 4 slots) and then it switches to Qbus in both the AB and the
CD sides.
Bottom line -- make sure you know what backplane you are plugging
boards into before you do so. Also, make sure that quad-high options
which can plug into both Q/CD and Q/Q have the CD jumpers on the board
set correctly.
Megan Gentry
Former RT-11 Developer
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At 11:20 AM 24-08-98 -0700, Jack Peacock wrote:
>>This is an old auction on eBay I happened to run across. Perhaps this
>item is still available:
>
>>MOOG Walter Carlos- Switched on Bach Mint Item #23979261
>
>Was there a reserve? I have one too, from high school days but hardly
>in mint condition, it's been played many times. For the last 15 years
>I've used a copy on cassette I still play every few months, the 3rd
>Brandenburg was a favorite.
Well it (and a lot of Carlos' other works are available on CD). I used to
use this sort of music to program to, but I'm more into the original
arrangements for programming now (not that I do a lot at the moment, but
there is this nice program I want to write for work that could end up
written in BCPL for old time's sake :-)
Huw Davies | e-mail: Huw.Davies(a)latrobe.edu.au
Information Technology Services | Phone: +61 3 9479 1550 Fax: +61 3 9479
1999
La Trobe University | "If God had wanted soccer played in the
Melbourne Australia 3083 | air, the sky would be painted green"
>> Myself, I prefer dancing and singing to celebrate things. What
happened
> to dressing up in costumes and building floats and giving away free
stuff
> like candy or food?
>Rape and pillage is far greater fun.
Robert Duvall said it best in Apocalypse Now: "I love the smell of
napalm in the morning. It's the smell of...victory."
In this case, victory over every bug-ridden PC ever made.
Jack Peacock
< I'm about to expose a lack of understanding of Q-bus, but do you need a
Dig up a PDP-11 Qbus book, most had a good description of the bus and
bus protocals.
< slot for uVAX-II memory given that it has the PMI (private memory
CDbus is used for PMI too.
< interconnect)? As you can tell, I'm not up there with Q-bus specifics an
< all the uVAX Q-bus systems I've used came with a suitable back plane (a
< vast cost at the time from Digital :-)
Makes it a lot easier.
Alliosn
>It never ceases to amaze me that, when offered an opportunity to
celebrate in a positive manner, groups of people will choose to smash,
burn and destroy things instead. If it were some kind of demonstration
against a particular company for some kind of social violations, it
least
smashing a computer made by that company would have some kind of
symbolic
purpose (albeit still a negative one). But to just smash something for
the hell of it.
How odd, seems like a natural thing to do. Many's the time I'd like to
have taken the PC under my desk, loaded it into the trusty old trebuchet
and slung it across the countryside. As for wanton destruction, don't
knock it till you try it. Last month I had the opportunity to fire a
75mm cannon at some cars, wasted a really nice Subaru. Then I got to
watch as the rest of the cars were strafed by a .50 Browning from a
helicopter. It's a great feeling to watch a Lincoln being blown apart.
We surely do live in the best of times.
Jack Peacock
< Well I'm not really a Qbus person. I never got into PDP-11s much and apa
< from adding and removing boards from a uVAX-II didn't get to play with Q
< much. The sort of thing I'm looking at is a little more sophisticated th
< "a bus is something that connects cards together" but a little less bori
< than a dry description of arcane features of signal timing and decay
< (although I've read plenty of these in my time).
let's see if I can do a little on this.
Q-bus DECs compaction of Unibus. Qbus is a time multiplexed, asychronous,
16bit data and depending on age of the system 16, 18 or 22 bit address.
It has termination and controlled loading to allow operation at high spped
using open collector drivers. While a 16 bit bus it also supports various
byte transfers. Q-bus is compact and fairly sparce in signals but supports
memory, device, interrupt and DMA transfers using the bus data lines and a
set of 10 control signals. There are other signals present for processor
control such as RUN, PowerOK and Binit are examples. There are more pins
than actual signals, some are redundant power for example. There are
lines for bus mastering, DMA and interrupt grant/ack are examples.
Most devices fall into several loose catagories, IO and memory.
The lower 16bits are multiplexed on the bus before every transaction using
the same lines data will be transferred on. Cards use BSYNC to capture
address and start any bus cycle that pertains to them.
Memory is fairly straight forward in that its timed off bsync and will
use the other 9 signals to synchronize it's operation. Transactions will
be read (word/byte) or write (word/byte). One of the characteristices
of PDP-11s is they always read before write (a read modify write cycle
is the normal thing). IO devices are identical to memory and by
convention and use of BBS7 are located in the top page of the 32KW
address space (1 11x xxx xxx xxx xxx).
The remaining transacions of not are interrupts and DMA. Interrupts are
posted via a request line that can be superceeded by another board
physically (buswise) closer to the CPU and will be granted by the CPU
to the higest(closest) requestor then and acceeding requesting modules.
When an interrupt is granted the board will place a byte(7 bits lowest set
to 0) VECTOR on the data bus that the processor will use as a pointer
to a table in the first 512byts of ram (interrupts vector table PSW and
interrupts service address is located in two words). DMA also has a grant
acknowledge and positional priority. Once granted DMA may proceed with
byte or word transfers of any length, though generally restricted to short
bursts to avoid hogging the bus.
The basic signals are:
BDAL 0->15-L -L denotes active low signal
BSYNC-L
BBS7-L Predecoded bank 7 signal (IO bank)
BAIKO-L Bus interrupt acknowledge
BWTBT-L Bus Write Byte
BRPLY-L Bus Cycle reply (must be supplied to continue the cycle
or a bus time out error occurs)
BDIN-L Bus Data IN toward CPU
BDOUT-L Bus Data OUT -> to module
Bus cycles have a distinct protocal (sequence) and timings.
< Does this narrow it down a little? I'm sort of surprised that there isn'
< nice description on the web somewhere....
Me too, though trivial it's not. I tried to avoid a description of each
line as that is quite lengthly.
Allison
At 04:48 PM 8/24/98 -0500, you wrote:
>
>< SMS300-1
>< 0002624
>< 001 A 7620 on it
>
>An early bipolar processor (very strange) that was often used for signal
>processing or stuff like hard disk controllers.
>
>Allison
>
Oh, you mean like a National 8X300?
Westen digital used 8X300's for awhile on disk controllers.
Alot of PC <-> Mainframe adaptors used 'em too . . .
Jeff
In a message dated 98-08-24 19:01:57 EDT, you write:
<< Here's a question: what _obsolete_ computer would you choose for this
miracle machine, assuming you have unlimited power? >>
how about any of the IBM family one series? there's plenty of them and no
shortage of them except for the 5155 and 5140 maybe. i'd keep those.
david
Plus consider that you could then ask for the smashed machines and
restore them. THere is unlikely to be any serious damage except
drives and CRTs. You could certainly scrounge the chips.
>> I think we should massively e-mail their chamber of commerce about
the
>> enormous stupidity of that event, this is an event supposed to
celebrate
>> technology not destroy it!
>
>If it is an XT, VAX, C64, Amiga, or whatever - I think humanity could
>spare one for a bit of fun.
>
>William Donzelli
>william(a)ans.net
>
>
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