Serial / COM on Handhelds

[Roger Garstang]

Anyone have any examples of this? The standard COM2 method doesn't appear
to be working. I'm probably going to have to use some low level as
even MSD reports them weird. It shows the normal IRQ/Memory locations but
reports a max speed of 3 for COM2.

These are old handhelds running an embedded DOS 5

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If you aim at nothing...you will hit it.

[Arthur Gomide]

Originally posted by Roger Garstang:
The standard COM2 method doesn't appear to be working.

Try a test with a loopback plug: if you send an "A" you must receive an "A" - adjust the baud rate accordingly to send/receive without framing errors.

Serial and Parallel Loopbacks
-------------------------------------------------------
If you wish to make your own set of Serial and Parallel
loopbacks, the pinouts are provided below.

WIRING LOGIC

9 Pin Serial - DB9S Connector (Female)

2  3  7  8  1  4  6  9
|__|  |__|  |__|__|__|

                               
25 Pin Serial - DB25S Connector (Female)

2  3  4  5  6  8  20 22
|__|  |__|  |__|__|__|


25 Pin Parallel - DB25P Connector (Male)

2  15 3  13 4  12 5  10 6  11
|__|  |__|  |__|  |__|  |__|

Edited: Start your tests with 300 baud.
I think that 3 baud is a graphic error!

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Arthur Gomide
Como diria nosso profeta da bola, Dadá Maravilha: "Para toda Problemática existe uma Solucionática!"



[This message has been edited by Arthur Gomide (edited January 30, 2007).]

[Roger Garstang]

It isn't the communication I can't do, it is opening the port all together. Dos is a little weird to begin with, but opening the port returns a timeout error. No data at all gets sent because the dock it goes through has a light that comes on and it is connected to a USR Ext Modem that also shows no activity as to being connected. The light on the dock never comes on. I'm going through the code for the other software that uses it since I remember some type of Bios routines, maybe it will show how they connect.

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If you aim at nothing...you will hit it.

[Arthur Gomide]

Originally posted by Roger Garstang:
It isn't the communication I can't do ...

Try testing the COM port hardware - use some tool, like ndiags from norton

------------------
Arthur Gomide
Como diria nosso profeta da bola, Dadá Maravilha: "Para toda Problemática existe uma Solucionática!"

[Mel Bishop]

Originally posted by Roger Garstang:
...opening the port returns a timeout error...

How are you opening the port? If you go:

open com2:2400,n,8,1

will give you timer issues, but if you go:

open com2:2400,n,8,1,rs,cs,ds,cd as #1

The rs,cs,ds,cd disables time considerations.



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[Roger Garstang]

Originally posted by Mel Bishop:
If you go:
open com2:2400,n,8,1
will give you timer issues, but if you go:
open com2:2400,n,8,1,rs,cs,ds,cd as #1
The rs,cs,ds,cd disables time considerations.

Tried both. I test my app with any normal PC port and it works fine.
It just isn't communicating with the handheld's port right.


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If you aim at nothing...you will hit it.

[Paul Franks]

IIRC, the last time I had to deal with a DOS handheld (years ago),
the serial port had to be powered up first. Don't remember, but I
think there was some proprietary API to power it up...

Later

No, my memory's faulty. I dusted off the manual (from 1996), and
it was the backlight that had to be powered on/off via proprietary
API.

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--pdf

[This message has been edited by Paul Franks (edited January 30, 2007).]

[David Gwillim]

If you are dealing with the old line of HP Palmtops (95LX, 100LX or 200LX)
you had to set an option in the built in configuration for the serial
port to make it power up when running in DOS. It was a battery saving measure
in the design.

Dave

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David Gwillim
Noesis Corporation, NY
noesisdgatverizondotnet

GAIA - the Mother of us all
Isaac Asimov's Gaia

[This message has been edited by David Gwillim (edited February 03, 2007).]

[Roger Garstang]

Setting something to turn them on sounds like it is needed. These are old
Fuji HHCs. They technically don't have a "port", but it has a couple metal
female contacts and some IR/IR Sensor arrays in the middle/bottom that talk to the
dock which has the port. The hardware level calls it COM2 though.

I was also recently informed that they are supposed to have Extended and/or
Expanded memory which I'm questioning since there is no driver loaded and PBDOS
doesn't detect it with the built in commands.

And to add to the fun the screens are only 20 chars wide. And I think
13 tall.

------------------
If you aim at nothing...you will hit it.

[This message has been edited by Roger Garstang (edited February 03, 2007).]