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From: prak2@pttrnl.nl
Newsgroups: comp.sys.amiga.hardware
Subject: Re: the parrallel port
Message-ID: <1991Jun27.111711.65105@pttrnl.nl>
Date: 27 Jun 91 10:17:11 GMT
References: <B92671994000426C@FANDM>
Lines: 23

In article <B92671994000426C@FANDM>, NJ_GOKEMEIJE@FANDM.BITNET writes:
> In my A500 introduction manual it says that I can use 100 mA of the
> Parrallel Port 5V line (pin 14). Unfortunately that seems not to be true:
> It looks like it is 5V over a 100 Ohm resister: if I draw about 20 mA, the
> voltage drops down to about 3V.
> (Or am I overabusing my power supply?)
> 
> Thanks, Nils Gokemeijer (NJ_GOKEMEIJE@FANDM.bitnet)

All power-outputs on the parallel/serial ports have this problem. 
They do have a resistor in their lines. This is done to protect your Amiga 
from being short-circuited by IBM-cables.
This feature is present on the A500 and A2000 (i guess for the A300 too, 
but i'm not sure). 
The A1000 does not have this problem because of it's non-IBM connectors 
for the parallel and serial ports.

You can solve this problem (if you want too), by by-passing the resistor. The
schematics can be found in your user manual. 
You will void your warranty if you do this.


jan.