single byte command

talhahs · Joined: 14 Oct 2010 Posts: 14

Hi all, I have to send single byte commands to sabertooth motor driver IC. Kindly tell me the difference between the two commands below:

FvM · Joined: 27 Aug 2008 Posts: 2337 Location: Germany

Only the first sends a single byte. The second sends three: 0x31, 0x32, 0x37.

talhahs · Joined: 14 Oct 2010 Posts: 14

Thanks a lot bro!

Well can you please explain how did you come up with [0x31, 0x32, 0x37] for 127 ?

gpsmikey · Joined: 16 Nov 2010 Posts: 588 Location: Kirkland, WA

The ASCII values for "1"= 0x31, "2"=0x32 and "7"=0x37 - three distinct ascii characters. I just recently purchased the new version of the compiler and in with the manual was a handy plastic guide with "C syntax tables" on one side and an ASCII chart on the other side. Actually a handy guide :-) Anyway, in the one case, you are sending a byte with the decimal value of 127 (0xFF) and in the second case (the printf()) you are sending a string of 3 characters 1,2 and 7. Hope that helps

mikey
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mikey
-- you can't have too many gadgets or too much disk space !
old engineering saying: 1+1 = 3 for sufficiently large values of 1 or small values of 3