Re: Doing NMEA command sequences with zsh ... ??!!

[Vasiliy Ivanov <beelzebubbie.logs@xxxxxxxxx>]

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On 13.10.2014 21:58, meino.cramer@xxxxxx wrote:
> 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

Not digging deep into NMEA stuff, only some related hints:

% integer a b; a=16#e7; b=16#3c; print $(([#16]a^b));
16#DB

% c='abcABC'; for i in ${(s..)c}; do print $((#i)); done
97
98
99
65
66
67




- -- 
Regards,
  Vasiliy Ivanov <beelzebubbie.logs@xxxxxxxxx>
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