Nascom News­let­ter

Here it would have been nice to be able to point to any error on the screen before the printer started printing. Unfortunately, this was not possible and the best solution I could arrive at was, having detected the error during printing, stop printing, print the Naspen line number where the error occurred along with an error code and then return control back to Naspen.

By this tine, all of the allocated space had been used and considerable effort was put into reducing the code required to perform the various functions, not wishing to remove any options or abbreviate the option menus. This entailed optimizing any code that was duplicated and/or adjusting routines so this could be achieved, along with the removal of any redundant code. Finally, some nine months later, it all slipped neatly into a 2K EPROM along with the inevitable bug or two which were later sorted out, with more code compression required. The ZEAP source code ultimately stretched to 21K.

There followed several weeks of documentation writing. The only difficulty here was getting all the information onto paper in such a way that other people could read and understand it. However, by the time it was completed, it had grown too large for a normal magazine article as I had intended, so, I submitted it to Micro Power for evaluation, after which you can guess the rest. So, a small word of advice to any would be programmers. If you think you have a good idea, get down and do something about it. It may not develope into anything, but you can not tell unless you try.

Finally, a brief description of what Nasprint-80 can do. It is a 2K, EPROM-based program which is normally located at B000H and which will operate at 2 or 4 MHz with either Nas-sys 1 or 3. It allows paginated or continous output from DEBUG, NAS-DIS, NASPEN, ZEAP and Nas-sys. With Naspen, however, up to nine different control codes may be embedded in the text to control the output format or the printer directly, during printing. Page lengths may be defined up to 255 lines with an optional title heading the page, and page number, at the foot of the page, from 0 to 999 beginning anywhere within that range. Both the title and page number may be placed in any position at the head and foot of the page respectively with the option of auto title centring if required. Page format changes, outside Naspen operation, are achieved by editing a default table before returning to the main program. All values used in the table are in decimal and default to standard fanfold paper (9.5″ x 11″). Output to the printer is via the Nascom PIO and no additional interface is required.

Although throughout this article I have specifically referred to the Epson printer, other parallel printers may be used. Should your printer not be compatible with Nasprint-80 your own output routine can be incorporated and substituted by giving its address as a second argument at initialisation.