<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=Content-Type content="text/html; charset=us-ascii"> <META content="MSHTML 6.00.6000.16441" name=GENERATOR></HEAD> <BODY> <DIV dir=ltr align=left><SPAN class=312442919-21052007><FONT color=#0000ff size=2>I would recommend "Inside CP.M" by David Cortesi. While it is not specific to Heath, it does a good job dealing with the CP/M OS. Here is a link to Amazon:</FONT></SPAN></DIV> <DIV dir=ltr align=left><SPAN class=312442919-21052007><FONT color=#0000ff size=2></FONT></SPAN> </DIV> <DIV dir=ltr align=left><SPAN class=312442919-21052007><STRONG><A href="http://tinyurl.com/33j35y">http://tinyurl.com/33j35y</A></STRONG></SPAN></DIV> <DIV dir=ltr align=left><SPAN class=312442919-21052007><FONT color=#0000ff size=2></FONT></SPAN> </DIV> <DIV dir=ltr align=left><SPAN class=312442919-21052007> <DIV align=left><FONT face=Arial size=2>Peter</FONT></DIV> <DIV align=left><FONT face=Arial size=2>----------------------------------</FONT></DIV> <DIV align=left><FONT face=Arial size=2>peter59@sbcglobal.net</FONT></DIV></SPAN></DIV><BR> <DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left> <HR tabIndex=-1> What is a good book on CP/M that is more relevant to H-89 spirit?</DIV> <DIV><FONT color=#0000ff size=2></FONT> </DIV> <DIV>ziloo</DIV> <P></P></BODY></HTML>