Re: problem with bcd and a number

Date	2011-08-04 13:14 -0700
From	Ethan Furman <ethan@stoneleaf.us>
Subject	Re: problem with bcd and a number
References	<31c8d075-2901-46eb-adcf-1c1803ab7938@a4g2000yqg.googlegroups.com> <4E3AF476.9050502@mrabarnett.plus.com>
Newsgroups	comp.lang.python
Message-ID	<mailman.1902.1312487936.1164.python-list@python.org> (permalink)

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MRAB wrote:
> On 04/08/2011 19:26, nephish wrote:
>> Hey all,
>>
>> I have been trying to get my head around how to do something, but i am
>> missing how to pull it off.
>> I am reading a packet from a radio over a serial port.
>>
>> i have " two bytes containing the value i need.  The first byte is the
>> LSB, second is MSB.  Both bytes are BCD-encoded, with the LSB
>> containing digits zX and MSB containing digits xy.  The system speed
>> is then xyz%, where 100% means maximum speed and would be given by
>> bytes 00(LSB) 10(MSB)."
>>
>> that is a quote from the documentation.
>> Anyway, i am able to parse out the two bytes i need, but don't know
>> where to go from there.
>>
>> thanks for any tips on this.
> 
> The value is MSB * 100 + (LSB >> 4) * 10 + (LSB & 0xF)

Not according to the docs -- msb has two digits, lsb has one and garbage.

~Ethan~

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Thread

problem with bcd and a number nephish <nephish@gmail.com> - 2011-08-04 11:26 -0700
  Re: problem with bcd and a number Ethan Furman <ethan@stoneleaf.us> - 2011-08-04 12:44 -0700
  Re: problem with bcd and a number MRAB <python@mrabarnett.plus.com> - 2011-08-04 20:35 +0100
    Re: problem with bcd and a number Christoph Hansen <ch@radamanthys.de> - 2011-08-04 21:52 +0200
      Re: problem with bcd and a number Peter Pearson <ppearson@nowhere.invalid> - 2011-08-05 16:01 +0000
  Re: problem with bcd and a number Ethan Furman <ethan@stoneleaf.us> - 2011-08-04 13:14 -0700

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