Re: VASM HP-41 question Message #2 Posted by Eric Smith on 22 Apr 2005, 2:45 a.m., in response to message #1 by Jeff D
They are just program labels. ad2-10, ad1-10, and ad2-13 are three different entry points for the addition ruoutine.
It's all explained in the comments at the top of the file.
Internally, numbers are stored in memory in 10-digit form. That's the count of the mantissa digits. There are also two digits of exponent, and one each of mantissa sign and exponent sign. There's also a 13-digit form that is used only in the registers, for intermediate calculations. That's 13 digits of mantissa, with the sign and exponent in another register.
For the 2-10 entry points, both numbers are in the normal 10-digit form. For 1-10, one is in ten digit and one is in 13-digit form. For 2-13, both are in 13-digit form.
For instance, the entry point ad2-10 is used to add two numbers both in ten-digit form.
Eric
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