I'm posting this message to the Developers Forum hoping that someone may
be able to help me with general information about Palm devices. The msg
below was submitted to [EMAIL PROTECTED] last week and I haven't heard a
peep. I've tried calling Palm directly, to no avail.
My client and I are looking at other devices that are targeted at serial
control; but the Palm device is an attractive package with what appears
to be a good development platform.
Any comments are appreciated!
-------- Original Message --------
Subject: Palm Application Questions
Date: Fri, 22 Oct 1999 15:27:02 -0700
From: Russ Pritchett <[EMAIL PROTECTED]>
To: [EMAIL PROTECTED]
I'm a consultant working a manufacturer of laser systems for scientific
and
OEM use. They have an instrument with an established serial control
protocol and would like to develop a remote control for this system
using an off-the-shelf, commercially available product. I'm inquiring
about using a Palm device for this purpose.
I've reviewed material in the development section of the web site and
have a few questions about this application as it relates to the Palm
environment. Let me say that the development tools (Code Warrior,
software emulators, etc.) look great, and I hope that I'll be able to
write an application for one of these devices.
1. The serial port on the instrument is a 3-wire connection (RD, TD,
GND). The instrument implements a XON/XOFF data flow control mechanism.
I noticed in the Palm serial port information that RTS and CTS hardware
handshaking are required for baud rates exceeding 2400 bps. This
apparently results from the small 8-byte buffer on the UART. Is there no
provision in the Palm OS Serial Manager for XON/XOFF flow control? Is
there any other way to increase the data rate without using the hardware
handshake?
2. For this application, my client would like to have the instrument
connected to the Palm serial port directly without using the cradle. I'm
assuming that if we participate in the "Serial Port & Modem Casing
Program" we will receive information concerning vendors who will sell us
(custom) cables for the Palm.(?)
3. This application requires the serial port to remain open to receive
unexpected error messages from the instrument. In one of the on-line
books, I read that typical Palm applications leave the serial port open
only long enough to transmit/receive data. This is done to prevent power
drain on the AA batteries (power hungry inverters are required to drive
the RS-232 signals). Is it possible to power the Palm over a dedicated
serial cable using pin 2(+3.3V) and pin 10 (SG) of the serial
connection? Do you know if this has ever been done before?
4. I'm assuming there is no non-volatile memory in the device without AA
batteries. If the Palm is powered over a dedicated serial cable, could
AA batteries still be used to produce 'non-volatile' memory between
power cycles of the instrument?
5. Also for the Palm powered over a dedicated cable, can the 'sleep'
mode be disabled using the Palm OS? If not, can the device 'wake up'
when a character is received on the serial port?
6. Is it possible to write an application using the Palm OS such that on
power up the application starts automatically?
Thanks alot for your time with these questions. Please feel free to call
at the number listed below.
----------------------
Russ Pritchett
650.728.0409
[EMAIL PROTECTED]
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