Re: [M100] Tandy Portable Disk Drive 2 service manual PDF now available.

2024-01-08 Thread Tim Russell
Thanks, I figured it HAD to be a typo, otherwise it would be rather ironic
for it to have more than 5x as much RAM as the standard 100 could support.

On Mon, Jan 8, 2024, 12:05 Darren Clark  wrote:

> I think the 128K or RAM is a typo and should only be 128 bytes. Looking at
> page 97 (set the data to drive's memory) and page 89 (get the data from the
> drive's memory), there is only enough room to request 125 bytes at a time.
>
> Also from my disassembly of the TPDD1 ROM and the very similar
> architecture (same CPU and RAM and CPLD), there is only 128 bytes of
> scratch ram.
>


Re: [M100] Tandy Portable Disk Drive 2 service manual PDF now available.

2024-01-08 Thread Tim Russell
Geez, up-front the manual said 128K of RAM!  I was thinking one could
reprogram the ROM to make it a ram disk for a sec there, but the parts list
only shows 2K of SRAM unless I missed something?

Anyway, thanks much for the efforts, all!  Great stuff.

Tim


On Mon, Jan 8, 2024, 10:23  wrote:

> The TPDD2 service manual in all of its glory...
>
>
>
> https://archive.org/details/tpdd-2-service-manual
>
>
>
> Jeff Birt
>


Re: [M100] M100 keyboard character map?

2021-10-27 Thread Tim Russell
Appendix O of "Hidden Powers" has a list, but not formatted in a nice
table.  Starts on page 237.

Tim


Re: [M100] Howdy! New to list, need some parts…

2021-07-17 Thread Tim Russell
Thanks for the Deoxit tip!  I have a Casio VL-Tone that has two scratchy
sliders but is otherwise pretty perfect for a 43-year-old device, may give
that needle bottle a shot.

On Fri, Jul 16, 2021, 22:56 Greg Swallow  wrote:

> Hey Earl,
>
> Welcome to the list.
>
> Deoxit on the pot. Amazon has it in a "precision" dropper here:
> https://www.amazon.com/dp/BYH6F8/ref=cm_sw_r_cp_apa_glt_fabc_HYHBJZ4YAQW7PX7RC30P
>
> Greg @ arcadeshopper.com has most parts you'll need. Including complete
> re-cap kits. Just picked up a couple kits with a replacement TPDD2 belt
> myself.
>
> God Bless,
>
> GregS <><
>
> Jul 16, 2021 5:03:08 PM Earl Baugh :
>
> > Howdy!
> >
> > I’m new to the list and recently picked up a model 100 that needed some
> restoration.  A friend helped me get the bad caps replaced, cleaned the
> power plug and we diagnosed a bad member switch and bad pot for the lcd
> contrast adjustment.  It’s working again (hurrah), with a solder bridge on
> the switch and some resistors temporarily in place of the pot.  ( we also
> removed the battery before any leakage or damage )
> >
> > Is there anyplace where I can get replacement parts for the pot and
> switch without digging thru a Mouser or Digikey catalog? (  or the part
> numbers at least to save a number of mis orders? )
> >
> > Earl
> >
> >
> > Sent from my iPhone
>


Re: [M100] User number in CP/M for M-100?

2020-10-06 Thread Tim Russell
The "user number in prompt" and "execute from user 0" thing are BDOS
extensions from a given manufacturer and not part of standard CP/M 2.2, if
I recall correctly.

It may have become standard in CP/M 3.0, but that's not really germane here.

On Tue, Oct 6, 2020, 17:26 Bert Put  wrote:

> Hello,
>
> I was wondering which version of CP/M that this was based on?
> I'm specifically looking for support for "user numbers" since CP/M does
> not support directories.  My Kaypro runs CP/M 2.2G and 2.2H.  In those
> versions, the user number is part of the prompt, such as A0> or A1>.
> Also, if you navigate to user area 1 with "USER 1", you can call any
> executable in user area 0 in case it does not exist in user area 1.
> There are 16 such user areas available, 0 to 15.
>


Re: [M100] REXCPM 102 - it's arrived - Let's Livestream an install!

2020-07-28 Thread Tim Russell
Very nice stream, Josh!  The whole time you were hooking the screen and
keyboard back up I was internally screaming "THE BOARD COVER!!" but I knew
you'd get it.

Tim


Re: [M100] REX3?

2020-03-12 Thread Tim Russell
I still have one, and a PX-4 as well.  Both can also use a battery-powered
serial-connected 3.5 floppy drive, which I also happily still have.

On Wed, Mar 11, 2020, 13:51 Tom Wilson  wrote:

> Also, if you're looking for an 8-bit CP/M laptop, the Epson PX-8 is
> exactly that. It runs CP/M from ROM and uses a RAM disk for storage.
> (Strangely, it uses a cassette for mass storage.)
>


Re: [M100] Somewhat off-topic, but... Epson CP/M portables?

2015-05-08 Thread Tim Russell
I have both a PX-8 and a PX-4, and I /believe/ they run straight off power
alone but am not positive.

If you can't get an answer let me know and I can experiment for you, both
are in a box in my room at home easily at hand.  They both have ramdisks
attached as well.

Tim

On Fri, May 8, 2015, 12:36 Christopher Barnett Fox cbfo...@syr.edu wrote:

 I just acquired an Epson PX-8 Geneva in pristine physical condition, but
 it won't seem to power up. I'm leaving the batteries to charge for 24-48
 hours, but I'm skeptical they have any life left in them at all.

 Should these old Epson portables run off the charger circuit alone? I
 think the Tandy Model T series adapters should be compatible (6VDC
 output, but only 500mA whereas I believe the original Epson charger was
 600mA), but I haven't had any luck powering the PX-8 just yet. I can see
 the LCD screen appears to turn on, but sliding the contrast only appears
 to make the screen uniformly slightly dark. Pressing the sub-processor
 reset button hasn't helped.

 Christopher