next version tannks Jan & Andy

comments still solicited

Erik


The '51 was never intended as a 'mathematical machine' but rather a process controller. The '51 is a microcontroller, not a microprocessor and, as such, has very limited mathematical processing capabilities. That fact and the fact it is an 8 bit device makes floting point slow and memory usage ntensive.

Many, many applications where the novice 'automatically' goes for a floating point package can be handled much more efficiently and faster by fixed point.

A variant of floting point that, as far as I know, does not have a name is what I would call "fixed math with inserted point" which fit the '51 as a glove.

Now what the heck is that you may ask. I will illustrate with an example (a Cash register).

$1,23 + $0.17, to a novice, seems like a natural app for the standard slow and tedious 'standard' floting point operation, but what is wrong with just doing 123 cents + 17 cents and inserting the decimal point on the display (and in the data stream to the printer), the user will never know the differennce.
The same method can be applied all over (instead of degrees use tenths of degrees, instead of kg use g ....