Article from Commodore Gazette 2, 1987

EDNA - The Professionals Assembler (Cover)

EDNA is an assembler for Commodore 64/128 that provides the average programmer with a valid development system for their own software. This product by Viza Software is one of the best in its category and offers possibilities that until now have only been found on larger systems; starting, for example, with the editor, which allows the creation of source code with almost the same ease as a word processor. All commands are easily accessible by pressing two keys that, in general, are easy to remember.

Assembly proceeds at a remarkable speed and incorporates numerous utility functions that can be switched on and off at the operator's discretion. It is possible to choose whether to assemble only in memory, only on disk, whether to display the symbol table, or whether to create the well-known assembly listing, which contains information regarding any errors made and the hexadecimal codes that are created during compilation. All of these latter possibilities can, of course, also be used in combination with each other.

The editor has been created with great care and provides commands such as copying, searching, moving, replacing and deleting words, phrases or blocks. It is from the editor that you select the I/O devices to use, you load, save, delete files and access DOS commands. Also from the editor you can concatenate all or part of the file in question with other files on disk. The assembly directives are truly numerous and versatile. Numbers can be expressed in decimal, hexadecimal and binary notation; a simple function allows immediate conversion from one base to another.

The editing area displays a control bar at the top of the screen that quantifies the memory in use and is divided into the usual fields label, instruction, operands and comment. The directives naturally allow you to enter data into memory both in numerical form and in character form. Many directives are curious, because they have never been found on other assemblers, such as conditional assembly, which allows you to choose which code to assemble when a certain condition occurs.

This possibility can be useful to simplify the passage to other computers, which is done simply by changing the specified condition; it is then the program that automatically chooses the part of the code that adapts to the system in use. In this regard, the user manual refers to the Commodore 8000 series , but does not dwell on how it is possible to obtain a file readable by this system.

Very useful are the «.LIB,» and «.FIL,» directives , which allow you to link to self-created symbol libraries or to use the one on the disk provided in the package, which contains all the entry addresses to the Kernal routines of the 64 and other addresses of various uses, such as the color registers and the location of the start of the screen. To work in direct contact with the machine, there is a carefully crafted monitor, equipped with a breakpoint function and step-by-step execution of a program.

It is possible at any time to return to Basic by reserving or, on request, deleting any source file present in memory. A very interesting possibility offered is that of managing a programming card for EPROM and EA-ROM memories . The manual, although rather concise, is very well done and written in fairly simple English. It clearly describes all the available commands and includes numerous tips for the programmer, describing how to use the routines created by Basic and explaining quite completely which memory areas are used by the cartridge.

For Commodore 128 owners there is a section dedicated to the description of the commands that the 65C02 processor makes available and that, of course, are also available in 64 mode and are recognized by the assembler. The disk supplied in the package includes, in addition to the Kernal 64 library , some setup programs, oriented above all to the management of peripherals, and a conversion program that allows you to use sources created with Mikro Assembler. A note of merit therefore to Viza, which with this new product maintains the high prestige rightly earned with its previous creations.

(C-64 / 128 in mode 64, cartridge + disk, Lit. 59,900).

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