mariana fiuba

8-bit arithmetic on 32-bit microcontroller

Discussion created by mariana fiuba on Jul 8, 2011
Latest reply on Jul 9, 2011 by TomE

This questiion goes to compare MC9S08 and ColdFire in speed.

How longer does it take a ColdFire core to execute a byte arithmetic instruction given that it works in 32 bits? I mean, in the 8-bit microcontroller, adding two 8-bit variabes is just that; but in a 32-bit microcontroller it needs to complete he 32 bits for each opperand firts, right? Should I give the ColdFire a higher bus speed to achieve the 8-bit variables addition in the same time?

Can anybody clarify this for me please?