Connecting to laptop serial port?
Frank Pappajohn
"definitively" answered. My question is: Is there any risk to my laptop if I
connect my Palm device's serial port connector (to sync it with my laptop)
while it's on? I should mention that the only software I run which (that I
know of) uses the serial port is the Palm HotSync software, and I *only*
start that application *after* I physically connect the cable to the serial
port.
I should also add that currently I only connect to the serial port when my
laptop is either on standby or hibernation. I haven't gotten the nerve yet
to connect while it's running. My question is basically, if I'm not running
a program which actively uses the serial port, is there any problem
connecting a piece of external hardware (the serial connector) to the port?
Thanks.
FP
Joshua S. Kraling
years now on my laptop with no probleems whatsoever....
HOWEVER, it is understood that you can do serious damage to the laptop (or any
computer) when you do this; or so I've heard. I guess I just like living on the
wild (or stupid) side.
Pax
Simon Lister
no problems as yet. The only time you are ever likely to have a problem is if
the serial device has some sort of fault and is outputting some strange
voltage. This is reasonably unlikely with the palm as it is a battery operated
device with an operating voltage less than that of the RS232 lines on your
serial port. I suppose it is theoretically possible (although it extremely
unlikely) for mains voltages to appear via the charger/cradle on a Palm V but it
would likely fry the palm first :)
In my experience I would say plug away. Even if you were running serial
software all the time it wouldn't do any damage to your PC.
The main problems which cause hardware damage is plugging in laser printers to
your parallel port while switched on. There are some extremely high static
voltages generated within a laser printer and if you are not careful they can
find their way to earth through you PC - although even this is relatively rare.
Del Monte
hibernate when connecting it.
As far as damage goes, I've seen a motherboard melted by a static discharge
from a PS/2 keyboard; the risk isn't worth it.
(Technically, the discharge blew a resistor on the board. The board melted
gradually, all the time running without
any indication of trouble, before it finally melted through the 6V power
rail. There are no experts when it comes to melting
safety margin topography :)
MSC
Frank Pappajohn schrieb:
budgie
<delmon...@hotmail.com> wrote:
>I use my Palm with my laptop as well, but I always either shutdown or
>hibernate when connecting it.
>
>As far as damage goes, I've seen a motherboard melted by a static discharge
>from a PS/2 keyboard; the risk isn't worth it.
The PS/2 ports are not only not designed for hot-plugging, but almost
all PS/2-supporting machines I have seen warn strongly against it.
Traditional parallel ports are TTL and are far from short-proof.
Traditional serial ports which met the RS232C standard were
short-proof and pretty much idiot-proof. All inputs and outputs had
to be able to withstand up to (+/-) 25V applied. Usually met with
series resistor and diode clamps.
Later VLSI implementations don't claim adherence to the elec specs of
RS232C but generally do have the same capabilities.
Now maybe it is obvious why serial ports use male D connectors and
parallel the more accidental_short_proof females.
Mark S
so no problem.
PS/2 port is definitely not so don't plug/unplug that port when the machine
is on.
/Mark
"Frank Pappajohn" <fr...@wizard.net> wrote in message
news:th60b0n...@corp.supernews.com...
Scott Persons
port connector plugged in while desktop is on...other end is a serial
port connector plugged in to the laptop when it's off?
Scott
Barry Watzman
any problems.
Barry Watzman
are longer than the signal pins so that it will work. Serial and parallel were not
specifically designed for it, and I have heard of it causing problems infrequently,
but in general you can do it and get away with it, problems, while perhaps possible,
are very rare.
Frank Pappajohn
FP
"Barry Watzman" <Wat...@neo.rr.com> wrote in message
news:3B1431F3...@neo.rr.com...
Peter da Silva
It's a damn shame the software on Windows at least isn't. I've had 2000 die
horribly many times when plugging in my Jornada when the cradle connector
bounced.
For software that has to deal with hotplugging, no conceivable failure
at the lower layers should crash the OS. Ever.
--
Rev. Peter da Silva, ULC. WWFD?
"Capitalism works primarily because most of the ways that a company can be scum
end up being extremely bad for business when there's working competition." -rra
Craig H. Ganoe
<fr...@wizard.net> wrote:
>[ ... ] My question is basically, if I'm not running
>a program which actively uses the serial port, is there any problem
>connecting a piece of external hardware (the serial connector) to the port?
If you're really concerned about it, get a USB to serial adaptor and
use that. It is safe to hotplug/unplug USB and the adaptors are not
that expensive.
Craig
Barry Watzman
serial adapters are not "real" serial ports, the only work for programs that
access the serial port via windows or BIOS. Unfortunately, a LOT of serial
devices try to do direct port I/O to the UARTs, and that won't work. So I
can't, for example, use my Qualcom 860 cell phone's modem capabilities with my
Toshiba 2805, which doesn't have a "real" serial port. And the same is true for
MANY other devices.
Although it's off-topic for the question asked, if a serial port is needed for a
computer (such as the 2805) that doesn't have one, a better choice is PC Card to
serial port, the PC Card serial ports actually ARE UART-based serial ports with
real uarts at the right port addresses.