[Coco] DMP printers, WAS --> Coco serial cable

[Rogelio Perea]

On Sun, Aug 30, 2009 at 3:47 AM, Christian Lesage <hyperfrog at gmail.com>wrote:

> wdg3rd at comcast.net wrote:
>
>> The DMP-105 was the successor to the LP-VII with a white case instead of
>> Mercedes silver.  To the best of my knowledge, that was the only change.
>>  Just as slow and noisy and just as crappy print.  (A dot-matrix impact
>> printer with only one pin is sort of limited from the start).
>>
>>
>
> Allow me to have my say in this incredibly popular thread!
>
> The DMP printer that was the same as the Line Printer VII was the DMP-100,
> not the 105. I know, 'cause I bought a second-hand one in 1986 or so, and it
> was crappy as hell. I remember writing at least three BASIC programs to get
> the most out of it. One of them was a graphics screen dumper. The second one
> would allow me to print the accented characters we use in French, because
> this dinosaur only supported the plain ASCII character set. IIRC, I would
> print a line of text without the accents, send a carriage return without a
> line feed, switch to graphics mode, and then add the accents over the
> letters that needed them in a second pass. Then I would revert to text mode,
> send a line feed, and repeat the process for the next line. Yes, printing
> time was doubled, so if you, English-speaking folks, think it was slow, just
> imagine how sluggish it was for me! The third program I wrote for this
> clunker would use the graphics mode for all text printing. I wrote it after
> I discovered (by myself) the HPRINT bitmap font in the CoCo 3 ROM, which had
> descenders and (almost all) accented characters. I was so excited when I
> discovered that font... and I immediately saw the opportunity to use it with
> the printer.
>
> I was 15, and had plenty of time, but no money. Those were the times...
>
> Christian


Back in the early 80s my school's fledging Computer Lab had 6 TRS-80
machines (four Model IIIs and two Model I's - the later the only ones with
floppy drives, rest was tape based). To service the printing needs only four
machines had LPVIIs.

The school was so negligent for that department that the last thing they
cared for was the replacement of the ink ribbons, at one time it got so bad
that we started to use double layered paper with a carbon sheet in between -
we would discard the faint almost impossible to read original and keep the
copy. Our requests for new ribbons went ignored more or less, and once the
admins got hold of our carbon copy workaround they thought they should care
even less.

We revolted. It only took one surreptitious ribbon re-inking that involved
the ink straight out of a BIC pen to make the school pay attention to the
evil doings of the lab admins. The affected LPVII had to be sent to the
local Radio Shack for "repairs", the price tag was that of many ink ribbons.
Soon after we started to see a steady stream of replacement ribbons appear
on those LPVIIs.

The things were noisy as hell, and slow, and no descenders - walking into
the lab in the middle of a printing frenzy was a memorable event. A couple
years after all of them had been phased out: the DMP-105 and DMP-106 showed
up in the RS catalog and the school bought a slew of them for the general
use workstations which now included IBM PC compatibles... the days of the
TRS-80s had passed.

I bought a DMP-106a for my CoCo 3 setup in 1988, it wasn't something I'd
call a high end piece of equipment but it endured all the homework,
newsletters, banners and other jobs I threw at it. I still have it and it is
in very good working condition.

An LPVII (or its DMP100 white clad offspring) seen on a thrift shelve? I
would pass.


-- Rogelio

-- Rogelio