Forums

How to choose a firmware partner

Started by robi...@tesco.net May 26, 2004
"Mel Wilson" <mwilson@the-wire.com> wrote in message

> >I would like to know as well. I worked on Honeywell 6000's and when
I
> >say early 80's, I mean July of 1980 and on. IIRC (and I think I do
;-)
> >they had about 128K words of core, and each word was 36 bits. They > > Talking '60s the GE-635 ancestor to the H6000 had > physical address space for 256KWords -- about a megabyte. > It doesn't look like more could be added, but it's not > entirely clear from the docs I have. The first Canadian > 635 installation was '64-'65ish. > H6000 physical address space could have been as much as 6 > "megabytes". The system I worked on was installed with > 512KWords. Enlarging to 768KWords exposed a bug in the > memory allocation software, so I doubt that they commonly > got that big, although physically it ran fine.
Cool, it's nice to meet someone that actually worked with this stuff before. I was beginning to think that everyone who had was dead now, or worse yet French. ;-)
<rpluim@spammers.not.welcome> wrote in message
news:t9aekp611py.fsf@spammers.not.welcome...
> > Absolutely - I (or rather my daughter) is adept at this. Set-top boxes
seem
> > to be particularly bad, and I believe I know why... > > Do tell. (I can crash my set top box in about 10 seconds without even > trying. Luckily it has a power switch on the front).
Brief version: this area seems to suffer from the Curse of The Inappropriate RTOS. Or perhaps it's appropriate, due to all the various 3rd-party comms layers required... but in any case, said RTOS doesn't seem to cope with processing key events terribly fast. Which seems kinda lame. The longer version involves the amount of times I've talked myself out of a job with set-top box manufacturers. Steve http://www.sfdesign.co.uk http://www.fivetrees.com
"Anthony Fremont" <spam@anywhere.com> wrote in message
news:Kdmtc.12165$lY2.9968@fe1.texas.rr.com...
> Cool, it's nice to meet someone that actually worked with this stuff > before. I was beginning to think that everyone who had was dead now, or > worse yet French. ;-)
Huh? Why French? Steve http://www.sfdesign.co.uk http://www.fivetrees.com
On Thu, 27 May 2004 00:56:12 GMT, "Anthony Fremont"
<spam@anywhere.com> wrote:

> >"Alan Balmer" <albalmer@att.net> wrote in message >news:bpq9b01m8va4ss24s9p6d7jgrtkv3alvvi@4ax.com... > >> We used them in the mid to late 60's on process control systems. On a >> dual system, the watchdog did two things - it switched the process >> control bus to the backup computer and rebooted it. The control >> database was piped once per second from the control computer to the >> backup on a high-speed core-to-core link, and the reboot took less >> than a second. This was from a head-per-track disk, and the biggest >> system had a whole megabyte of memory, so it didn't take long :-) > >A full megabyte....in the 60's?....that's pretty big. I programmed on >WWMCCS GE/Honeywell mainframes in the early 80's that didn't have a full >megabyte of magnetic core memory.
These were Varian (later Sperry, then SSCI) machines. The originals could handle only 64 MB, as I recall. Our earlier systems sometimes shipped with less than that. Later, they introduced the "Megamap" which extended addressing capability to a megabyte by use of page mapping registers. I don't remember when the Megamap was introduced. It might not have been until the V-70 series. -- Al Balmer Balmer Consulting removebalmerconsultingthis@att.net
On 27 May 2004 02:30:14 -0700, robin.pain@tesco.net
(robin.pain@tesco.net) wrote:

> >If your system is simple enough to predict this, then it is simple >enough to code without the risk of depending on state to avoid lockup.
That explains your statement, I guess, but you misunderstand the purpose of the watchdog. It's not to protect against coding errors. Hardware breaks. -- Al Balmer Balmer Consulting removebalmerconsultingthis@att.net
Steve at fivetrees wrote:
>Absolutely - I (or rather my daughter) is adept at this. Set-top boxes seem >to be particularly bad, and I believe I know why...
Are you referring to a Sky digibox by any chance? I have to reboot mine at least twice a week. Andy
On Thu, 27 May 2004 11:08:28 GMT, bastian42@yahoo.com (42Bastian
Schick) wrote:

> >>>In the very late '60s I worked on a UNIVAC 1110 which had that >>>much memory but I can't say now if it was core or semi. >> >>Are you sure it wasn't an 1108 or 1106? The 1110 was introduced on >>November 10, 1970. (Many web pages say 1972, but they are wrong.) >> >>The 1110 had a full megaword of memory, which is over four >>megabytes (36 bit words). It also had plated wire memory in >>addition to the core. In 1976 the 1110/40 came out, which was >>an 1110 with a megaword of (faster) RAM chips instead of core. >> > >Forgive my ignorance (I was released 1970), what is the difference >between core and RAM chips ? > >
Anthony gave a good description. Keep in mind that many of us old farts have a tendency to call even semiconductor memory "core." In fact, crash dumps are still called core dumps even by people who never saw any core <g>. There are interesting pictures at http://www.antiquetech.com/history/miscellaneous_pictures_of_core_m.htm and http://www.pdp8.net/pdp8em/pdp8em.shtml among others. I remember when core prices finally were reduced to the long anticipated goal of a penny per bit. One of the good features of core was that it was non-volatile. In the early days of semiconductor memory, it was a hard sell in the process control industry because it would lose it's data if the power went down. We sold battery backed up memory because of this. Still, it was somewhat unreliable, so all our memory was ECC, self-correcting for 1-bit errors, and detecting >1-bit errors. -- Al Balmer Balmer Consulting removebalmerconsultingthis@att.net
Anthony Fremont wrote:
> "42Bastian Schick" <bastian42@yahoo.com> wrote in message > > >>Forgive my ignorance (I was released 1970), what is the difference >>between core and RAM chips ? > > > Wow, do I feel old now.
No kidding. Did anyone else have the high school algebra book that had a picture of a core plane on the cover? Latest technology then. Magnetic core was a bunch of tiny little
> "donuts" that looked something like miniscule ferrite beads. It was > literally sewn together by meticulous women (peering thru microscopes) > into an X, Y type lattice that also had a sense/inhibit wire running > throughout all the "donuts". Each little donut could be magnetized into > one of two polarities to represent a 1 or 0. When core was read, it > destroyed the data stored and had to be automatically rewritten by the > hardware. Some guy named Wang figured all this out. >
On 2004-05-27, Anthony Fremont <spam@anywhere.com> wrote:
> "42Bastian Schick" <bastian42@yahoo.com> wrote in message > >> Forgive my ignorance (I was released 1970), what is the >> difference between core and RAM chips ? > > Wow, do I feel old now. Magnetic core was a bunch of tiny > little "donuts" that looked something like miniscule ferrite > beads. It was literally sewn together by meticulous women > (peering thru microscopes) into an X, Y type lattice that also > had a sense/inhibit wire running throughout all the "donuts".
Back in 1985 I had an interview at one of the last places that still made core memory (there was still military gear being built with core). It was pretty impressive in a retro sort of way. The toroids looked like rounded black grains of sand. The holes in the middle were not casually visible to the naked eye: if you knew the holes were there you could just barely see them under just the right lighting. Once woven together, a sheet of the things looked like a shiny, coarsely woven fabric. The place only had a couple women capable of stringing the beads. They were a bit worried that one of them would quit or die or whatever before they EOL'ed the product, since finding/training a new person was quite time-consuming. -- Grant Edwards grante Yow! I'm into SOFTWARE! at visi.com
"Andy Sinclair" <me@privacy.net> wrote in message
news:921cb0dvc3pdjphsbq6ran7fqkb84b0d30@4ax.com...
> Steve at fivetrees wrote: > >Absolutely - I (or rather my daughter) is adept at this. Set-top boxes
seem
> >to be particularly bad, and I believe I know why... > > Are you referring to a Sky digibox by any chance? > I have to reboot mine at least twice a week.
I've had a Sky box, and yes, it was fragile. I was actually referring to my Nokia freeview receiver - which my daughter (she of the phn txt skl) manages to crash in seconds. Steve http://www.sfdesign.co.uk http://www.fivetrees.com