In case anyone is interested I have a language definition file for the free Notepad++ (https://notepad-plus-plus.org/) that provides support for HLASM syntax. Not as extensive as the Z Open Editor, but probably easier to get going with, especially if you are already a Notepad++ user.
It recognizes and highlights all of the machine mnemonics through about the z13 or z14 and all or most of the assembler directives and instructions like ACONTROL and AMODE. It highlights registers AR0 ..., R0 ... It highlights the fairly common z/OS macros like ABEND, ALESERV, ASASYMBM, ... It is supposed to recognize * comments but there seems to be a bug in Notepad++ that makes comment recognition a little intermittent. (No recognition of "field 4" comments - comments like SR 0,0 This is a comment.) Recognizes the filename extension .zasm It's easy to edit if you want to add or change things using standard Notepad++ language definition facilities. Free for the asking. No warranty or support! Use at your own risk! A private request would probably be the best: charlesm at mcn dot org Charles
