Register Sizes and Usage

Harsh Pawar · New User Joined: 04 Jun 2008 Posts: 25 Location: Noida

I have some questions:

1) Some times we say 8 bytes registers and sometimes we say 4 bytes. On what factor the register size depends?? is it addressing mode or is it architecture (like Z/os has 8 bytes register) ?

2)When we give addressing mode (AMODE) = 31 then what is the need of specifying RMODE?

3)We can address 32 bits from a 4 byte register then what is the need of 8 byte registers ?

I know these are very basic questions but i am curious

Thanks for helping.

Regards,
Harry

dick scherrer · Posted: Tue Jul 21, 2009 11:35 am

Hello,

When you have a question, you should start a new topic for your question rather than post a reply to some 3-year old, inactive topic.

You might look at this previous topic as it explains some of what you are asking about.
ibmmainframes.com/viewtopic.php?t=10564

Please post a reply here if something is not clear.

Harsh Pawar · New User Joined: 04 Jun 2008 Posts: 25 Location: Noida

Thanks , that answers all.......

dick scherrer · Posted: Tue Jul 21, 2009 9:31 pm

You're welcome

d