Tutorial for review please!

Oldbitcollector (Jeff)

I'm working on an introductory tutorial designed to move very quickly into basic spin programming with some simple LED demos. I'd really appreciate some feedback on this.


http://dl.dropbox.com/u/7557533/temp/Propeller%20Programming%20First%20Steps.pdf


Thanks gang.

OBC

Dave Hein

The line that reads

  dira[16..22] := %1111_1111  ' Set P0 thru P6 to output

Should probably be

  dira[16..22] := %111_1111  ' Set P16 through P22 to output

Only 7 bits are being set, so the constant only needs to be seven ones. Of course, eight ones would work also. The word "through" is better than the abbreviated term "thru" for people where English is not their first language.

Also, the range 16..22 is bit-reversed from the normal bit ordering. It may be less confusing to use 22..16, but either form is OK.

Dave

Oldbitcollector (Jeff)

Exactly the reason I'm posting it here! A second set of eyes!

Actually, the demo will be increased to 8bits. I seem to have misplaced one when I was transcribing the text from a different board I was using here.

Thanks!

OBC

Dave Hein

I read through the tutorial again, and the 16..22 form is OK at this point, but it will need some explaining later on when you show that OUTA can be written to as a 32-bit value. You should explain what the "%" character means before the 1111_1111 digits.