I downloaded the stuff from the svn, got it to build, then did a cmp -l on the load file from my assembler vs. the one built from the svn tree. There is a bug in the svn sources on page e09-07, near the bottom. The call to sleep should read: jsr r0,sleep; 0:.. Note that there should be a colon, not a semi-colon after the 0. Presumably, this code was never executed, else it would have resulted in a halt. After I made that fix, a build from the svn tree is identical to that from my assembler. James Markevitch