5 Mar
2011
5 Mar
'11
11:24 a.m.
For the SS80 protocol in a microcontroller, it could be done easelly.
If you look at hp-7908.c file, there is very few microsoft dependancy
(only writing and reading from a file which should be replaced by reading
and writing to an sd card) the rest is just 2 circular buffers (it could be one
of 9 bits data), a state machine and some functions to read and write to the
buffers.
Read and write from those buffers will be the more delicate to make because
they should completely implement the 3 wires handshake of HPIB.
On the emulator I only made the 3 wire hanshake for controller to instrument
it was enough.
By looking at picture from hpmuseum.net, i think that every model got
is own charset
as they don't share the same size of charcell on display.
9816 got one, 9826 another one, 9836 & 9836C certainly the same, 9837
another one
From the various doc I read, I think the HP898204A and
HP898204B
should have the
same charset (but who knows) as the 9836.
Olivier
2011/3/5 Tony Duell <ard at p850ug1.demon.co.uk>:
The GPL V3.0 licence is included in the source archive of course.
For the other project, someone already get the verilog HP86 in FPGA I
have on my site
to try to make this kind of stuff for amigo protocol.
For fpga, I use a digilent evaluation board and the free tools from
xillinx (they exists for windows and linux)
The source for the whole HP86+HP9121/HP9895+serial line in verilog is
gpl too ....
It not very complicated, just some componentt to adjust levels, some
buffers to map
the inout nature of HPIB lines into IN part and OUT part for the fpga
(it better this way),
I was thinking that it should be fairly straightforward to bit-bang HPIB
through the port pins of a microcontorller (HP did this in some of their
machines, the 98034 uses an HP custom Nanocontroller chip, and IIRC the
82169 uses an 8049with an HP buffer chip). That microcontroller could
also handle the SS/80 protocol and SD card interfce.
Of course an FGPA could do those things too, so if somebody wants to make
a version fo this in an FPGA that would be great.
Btw as you 'distmantle' regularly your
series 200 machines, do you
think if it is possible to dump the
rom of the character generators in the alpha part of the display board ?
Sure. The ones that would be easiest for me to get to are the 9836C
(colour) and HP98204B (video card in the HP9817). I think I couldget to
an HP898204A card too. Do you want more than one character generator
dump, or is any one OK. Given the choice I'd rather do one of the 98204
ones, simply becasue it's easier to pull a DIO card and desolder the ROM
than it is to dismantle a 9836 far enoguh to extract the video boards,
but either is possible.
-tony