Stock Control Keep efficient control of your stock with this splendid program written by Neil Streeter of Hastings. This program for the 16K ZX81 allows the handling of stock control files. Each file set up will deal with up to 100 stock items and willl tell you which items require re-ordering. The program itself is menu driven and offers nine main options: you may enter or delete stock; enter the amount re-ordered; delete files or enter new items; save the file; or print out a list of all stock items and suppliers via the printer. The subroutine for each option appears starting at line number 1000 multiplied by the option number. These are called in line 390 by GOTO 1000*I, where I is the option chosen. The option to save a file under a file name allows the facility to run several files, where each file contains stock of a certain kind. For example, one file could deal with food stock, another with sundries, and a further file could deal with stock for the office. In this way, it would be possible to have as many stock items as you wish on file. A further program could then be written, by the more enthusiastic of you, to index the files and what they contain. As a last note, the product reference code should be unique to each item and should not be a sub-code of another item. For example, if you enter a code, food, and there already exists a code of this name, the computer will return the first found. However, the entry of the new items routine will tell you if a code already exists, do this should not cause any problem. Spectrum conversion The program is fairly straightforward and the listing self explanatory, and can be converted to run on the ZX Spectrum with minimal alterations. First, alter the number in line 100 to 50 for the 16K Spectrum and 250 for the 48K Spectrum. [I have decided, instead, to have the program choose the number itself depending on the system variable RAMTOP. This way, the one program will run with either size memory and use it all. However, it seems that the author of this article over- estimated the memory of the 16K Spectrum - I had to lower its allotment to 35 items for it to fit.] Then, delete all the lines with FAST or SLOW in them. Finally, you may wish to change all the upper case messages to lower case, but this is not absolutely necessary. [Oh, yes it is!]