Hi James,
My idea 3 years ago was to build the physical TDock board. And I
actually built a board, though never got it working yet. It is PiHat
for Raspberry Pi B with a 5V tolerant Xilinx CPLD to interface with the
Model T via parallel port. The TDock software is directing all screen
I/O to the parallel port using "special" signalling. What this means is
that it raises the STROBE signal and then twiddles the D0 - D7 data bits
to send data. The TDock server (VirtualT emulation, physical TDock
CPLD, etc.) detects this D0-D7 signalling and realizes it is the TDock
software communicating vs. the ROM trying to send LPT data. The ROM
*never* changes D0-D7 while STROBE is HIGH, so it is easy to know it's
not the ROM wanting to print.
Then TDock CPLD decides that it received SCREEN data and passes it along
to the output device (VirtualT window or Raspberry Pi HDMI port, etc.).
At least that was the plan. If the TDock CPLD detected LPT print data,
then it would send the printer data to it's LPT replacement port. In
other words, TDock hardware consumes the LPT port on the Model T, but it
is generous and gives it back on a different connector (one of it's
own), so you can have your cake and eat it too.
I have all of the CPLD code written and even working in simulation (I
wrote a verilog testbench to emulate all of the signalling an it is
supposed to work in theory). But I didn't get it working on the board
... probably because I simply ran out of time before getting too busy
with work and kids.
Ken
On 9/14/18 12:36 AM, James Zeun wrote:
Very interesting Ken
I've never actually used virtual T, as I only ever use my M100. Would
this process aid others in getting a physical M100 to output to a monitor?
I wasn't clear whether this only applied to emulation. Which is
obviously very handy, but not much use to those of us rocking a
physical machine :-P
Many thanks
James
On Fri, 14 Sep 2018, 12:27 a.m. Ken Pettit, <[email protected]
<mailto:[email protected]>> wrote:
All,
Attached are three files TDOCK.CO <http://TDOCK.CO> file for
M100/M102 and CCHART.DO /
CCHART.BA <http://CCHART.BA>. The TDOCK.CO <http://TDOCK.CO> file
is the binary output of the code I was
writing for the DVI replacement solution called TDock. VirtualT 1.7
emulates TDock.
Load this to the emulation and from BASIC exectute:
clear 256,62400
loadm"tdock.co <http://tdock.co>"
This will load TDOCK to address 62400 in high RAM but will not
install
the TDock / DVI "hooks". To install the hooks and thus activate
TDock,
issue
call 62400,1
This will print the TDock copyright screen
Once the TDock hooks are installed, from BASIC you can get an 80 x 25
screen by issuing:
screen 1
width 80
Go back to the regular screen mode with "screen 0". Note that the
80x25
window is EXPERIMENTAL ... it has no options for resizing, the menu
items on the top are non-functional, and if you close it while you
are
in active "screen 1" mode (i.e. the cursor is on the emulated DVI
screen), VirtualT WILL crash.
To "uninstall" the TDock hooks, issue
screen 0
call 62400,2
no notification given, but "screen 1" should no longe work.
The CCHART.BA <http://CCHART.BA> / CCHART.DO files (one tokenizd
BASIC, the other TEXT) are
an example application that draws a color chart on the emulated DVI
screen. You must first go into BASIC and issue the commands:
"screen1"
and "width 80" before this BASIC program will work. Hit CTRL-C to
exit out.
Ken
On 9/13/18 3:05 PM, Greg Swallow wrote:
> How is it enabled/activated?
>
> God Bless,
>
> GregS <><
>
> ----- Original Message -----
> From: "Ken Pettit" <[email protected] <mailto:[email protected]>>
> To: [email protected] <mailto:[email protected]>
> Sent: Thursday, September 13, 2018 12:27:58 PM
> Subject: Re: [M100] DVI or modern equivalent
>
> VirtualT 1.7 supports DVI mode :)
>
> Ken
>
>
