No Subject

[jfox@xxxxxxxxxx (Jeff Fox)]

>What is the programmer's input device to this system? I know, that Chuck
>would favor a joystick under OK -- four arrow keys and two (or theree?)
>buttons. This might be fun, I'll try it :-)

OK uses 7 buttons, 4 arrow keys, and three function keys.  It also has
an 8th function which is timeout.  I have been looking into substituting
a mouse.  I could provide the same 7 functions.

>On the other hand, if one would like to type source code, some interface 
>to a keyboard is needed. How would one be connected?

I just connected an old parallel ascii keyboard that I got for $12 surplus
in place of the 7 pushbuttons using a different cable.

>Anothor question is the mass storage. Is the PCMCIA interface functional? 
>Can type I-II-III storage devices be attached to the system? 

The MuP21 boots from 8 bit memory.  This is a pcmcia sram card on the first
development systems, and a uvprom on the later kit type boards.  I
have a jumper so I can connect a PCMCIA card into the UVPROM socket.  I
can prototype the PROM this way, and the block i/o routines work for
both read and write on an sram card.  On a UVPROM it is read only.

PCMCIA cards were RAM only originally.  Today they have 8, 16, or 32 bit
data busses, and an extra pin decoded or i/o.  This is how they support
modems etc.  MuP21 uses the 8 bit sram interface to boot, so a pcmcia
card can be used for booting.  With a little more decoding logic you
could have two cards, or boot from uvprom and have something else at
the other end of a pcmcia connector.

I have not experimented with FRAM/UVPROM/OTP/modem/lan/wireless/analog/
vga/gps/radio/infrared/hard disk/ or any of the other PCMCIA peripherals.
But I plan to.

Type I,II,III,IV just refers to the thickness of the cards.  Old cards
are I about 2mm thick.  Type II is 5mm, Type III is 10.5mm.  There are
hard disks in type II and type III,  20 to 480 meg.

There is currently no software support for any exotic PCMCIA cards from
these chips.  Drivers are normally written for BIOS on a PC.

I would like a development  board with a dual PCMCIA connector, uvprom
socket, and the high speed sram chips....

The PCMCIA specs are conservative, and they want you to buffer i/o
and do other things to provide safe hot insertion and removal of
cards etc.  MuP21 really just treats the PCMCIA interface as a 64
megabyte SRAM.  You will have to provide an I/O signal from MuP21 to
the connector, and write software to use any of the i/o devices
that I mentioned.

>The next question, that arises is the transfer of data from other 
>computers (a PC maybe) to the MuP21 realm. But this may be done with the 
>parallel port, I guess.
>
>Of course, if one has a PC, one might actually use the PC as a terminal and
>mass storage over the parallel port, but this setup is less flexible. I
>personally woulg like to be able to put the system, keyboard, mass storage
>and power supply in a bag and be able to work anywhere on the road, where 
>I can find a TV set.
>
>--
>Penio Penev <Penev@venezia.Rockefeller.edu> 1-212-327-7423


The P21Forth has vectored i/o, it is easy to do.  I can run with a pc
as a terminal/mass storeage device or I can run stand alone.  Any
combination of serial i/o, parallel i/o, and video output may be
selected.  I can run portable with a few batteries or a solar array,
or I can connect up to a PC.

Jeff Fox