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Date: Mon, 13 Oct 2014 17:58:06 +0200
From: meino.cramer@gmx.de
To: zsh-users@zsh.org
Subject: Doing NMEA command sequences with zsh ... ??!!
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Hi,

To my embedded system (which runs zsh on Gentoo Linux ;) ) I have
atteched an GPS receiver chip.
This chip spits out NMEA sentences to an UART and is capable of
receiving NMEA command seqyences.

An NMEA command sequence consist of
$<commandname><parameter,nextparameter,....><*><checksum>

The checksum is the binary XOR of all characters between '$' and '*'.
This checksum is given a an hexadecimal number.

Since it is an embedded system, I would prefer to calculate this
checksum with zsh only since it already runs if I am logged in.

Is that possible in any way?

Thank you very much in advance for any help!
Best regards,
mcc