Nixdorf 8812浮点数

Question

I'm currenty working on a cashier system software and stumbled over 32 and 48bit Nixdorf 8812 floating point numbers. For example:

A4 38 76 00 00 00 or A4 35 97 00

I suppose the first bit is for signed numbers, but what is the exponent?

Edit: Found out that the first "4" means the position of the decimal separator. All numbers after that are packed decimals. The "A" seems to be the sign. But this is just a guess. The total amount matches btw!

Answer 1

Maybe it's a variant of IEEE 754? :)

https://en.wikipedia.org/wiki/IEEE_floating_point

Can you create arbitrary floating point numbers at look at their binary representation?

Like 0.0, +0.0, -0.0, +1.0, -1.0

And if you can, could you post them here? 😁

Answer 2

Example: A4 35 97 00 -> 35,97

The "4" was the decimal separator. I didnt find out what the "A" means.