Can anyone give me any general hints for common mistakes to look out for or logic errors I may have?

1) assuming "logic errors" mean syntax errors:

http://www.metaice.com/ASM51/ASM51.htm will give you the metalink assembler and the documentation which, for a freebie, is excellent.

Write your code using that and look up the error codes it generates - that will get you there.

BTW, if you're familiar with Reads51

I'm not, but I had a look and was not impressed.

2) assuming "logic errors" mean structural errors:

The most common problem is a forgotten '#' as in mov a,10 instead of mov a,#10. I can not think of any other "common" mistake. Anyhow, do not make the mistake of "comments can come later" no comments = inability to debug.

Erik