First, excuse me for my bad english.

I just bought a HP33s as a replacement for my HP32sII which if fallen from my desk

I use the HP33s in RPN mode and I have just written a small program that I used 20 times a day with the 32sII

The aim of the program is to compute the total area in cm² of y circles of radius x (in mm)

This is very, very useful for my job (steel reinforcement in concrete)

I enter data in this manner : number of circles ENTER diameter in mm then XEQ A

The program :

A0001 LBL A

A0002 x²

A0003 400

A0004 /

A0005 pi

A0006 x

A0007 x

And that's all.

With the HP32sII the answer was only in the x register of the stack.

With the HP33s, the answer is in both register x and y. And this is a BIG problem for me (I use the program several times in a row and I sum the answers)

I have tried the program by entering manually the instructions, and so I only get the answer in the x register ! So my program is correct !

I've tried 36 tips in the program to change this (for example, A0008 R(low)). But with every tip I get answer in both X and Y or no answer at all

Precision : I begin data introduction when all registers of the stack are at zero

Does someone has an idea ?

Does the stack behave differently between HP32 and HP33 ?

Thanks a lot

David