[Coco] What are you tankful for this Thanksgiving?

[Gene Heskett]

On Thursday 22 November 2018 09:10:09 Neil Cherry wrote:

> On 11/22/18 12:13 AM, Aaron Davis via Coco wrote:
> > i blame myself for starting your 1802 habbit.
> > --------------------------------------------
> > On Wed, 11/21/18, Melanie and John Mark Mobley
> > <johnmarkmelanie at gmail.com> wrote:
> >
> >   Subject: [Coco] What are you tankful for this Thanksgiving?
> >   To: coco at maltedmedia.com
> >   Date: Wednesday, November 21, 2018, 4:55 PM
> >
> >
> >   I am also thankful for the RCA 1802
> >   microcontroller.
> >   I am running the Emma 02 emulator for
> >   the 1802 "Membership Card".
>
> I have half of a very odd 1802 system called a Dage MC-3. I managed
> to dig up the 1992 Radio Electroncs articles on it. But while playing
> I wanted to use an emulator since I'd not worked with the 1802 before.
>
> I found a Javascript COSMAC ELF emulator that was broken, told the
> author and he responded: "No it wasn't" (???) So I copied it down and
> went about patching it up. I put it here and at the moment I can't
> recall how to use it.
>
> https://ushomeautomation.com/Projects/SimElf++/index.html
>
Thats a CosMac Elf?  Looks almost homemade.  The CosMac Super Elf I used 
at KRCR-tv was a made pcb, and had a 6 digit display, so both the 
address and the data at that address were displayed. Had a space at the 
top edge for an s-100 socket to be soldered in and a hex keypad with 4 
extra keys. This board probably doesn't have some of the functions in 
hdwe that the emulator expects to be present.

> It works pretty well and I'll probably revisit it at some later date
> to clean up it a bit more. I do recall having the 'serial terminal'
> working. It still has several bugs.

Do you have a copy of its manual, the MPM-201C? About 122 pages, has all 
the internals, and a list of the op-codes in both hex and nemonic 
shorthand for an assembler I never had.

Because the sw I wrote on it was heavy with repeat functions with only 
the timing changed, or addresses into the font table, I used a lot of 
self-modifying code. When its instant job had been finished, I had it go 
around and restore the initial values of all the mod-ed locations. Dead 
stable, couldn't crash it. When I left, I left the next tech 
instructions on how to change the machine ballistics in case the machine 
got replaced with newer tech. After I had come to WV as the CE at WDTV, 
and had changed wives, I took my new one of about 5 years to Portland to 
meet one of the last surviving aunts of mine who lived in Salem and was 
nearing the end of her time, and one of the things I did while there 
in '94 was to call KRCR and ask Norman, the CE there, what had become of 
the gismo I left in '81. They were still using it quite a few times a 
day! In a tv station control room equipment often gets replaced with 
newer stuff on a 5 year amortization schedule, so that 13 years was 
amazing. But no one ever offered a commercial replacement for a very 
handy production tool, one that enabled the tapes to be formatted with 
control tones on the 2nd audio channel to queue the tape to its starting 
location, even to installing a new digital countdown in front of the 
video start, then at the end of that commercial to start the next 
commercial in the next machine. You could do a 5 commercial station 
break with one button push if you had 5 machines.

Today of course its all on hard drives, many terabytes of them. And the 5 
second pre-rolls needed to get stuff in synch with those early machines, 
the "ballistics" is now 20 milliseconds. Time marches on.

> At the moment, I'm doing more work with the sbc09 emulator (posted to
> github: https://github.com/linuxha/sbc09) which I'm using with t
> he 
> Sardis ST2900, the SWTPC 6809 and to brush up on the CoCo asm.
>
> --
> Linux Home Automation         Neil Cherry       ncherry at linuxha.com
> http://www.linuxha.com/                         Main site
> http://linuxha.blogspot.com/                    My HA Blog
> Author of:    	Linux Smart Homes For Dummies

Happy Thanksgiving Neal.

-- 
Cheers, Gene Heskett
--
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>