80-Bus News


March-April 1984, Volume 3, Issue 2

Page 32 of 51


The internal power supply of the progammer provides all the necessary voltages, and no power is drawn from the main system. As well as the various programming voltages (25V, 21V, 12.5V) the EPROM supply voltage can be raised to 6V, the level necessary if the “intelligent programming algorithm" is to be implemented for the larger EPROMs (see below).

The programmer’s box is made of metal and consists of an interlocking U-shaped base (coloured black), and a U-shaped lid (coloured grey). With the metal construction of the box and the internal mains transformer the weight of the programmer is such that it sits nicely on a flat surface without any tendency to scoot about while EPROMs are changed. Taking the lid off the box reveals a very neat and compact arrangement. The main programmer logic is contained on a single PCB that runs the length of the box. Underneath this PCB is a toroidal mains transformer and a smaller pcb that carries the power supply components.

The Disk: This holds three programs:– PROG. COM The programmer software. CPROG. COM A configuration program for PROG.COM PROGINIT.MAC The low level assembly language drivers used within PROG.COM.

The disk is in Gemini QDSS format (i.e. single sided Galaxy format – 96tpi) which can also be read by double-sided sytsems (QDDS format). The manual indicates that you should be able (via your dealer) to exchange it for DDDS or SDDS formats (the early Gemini 48tpi formats). Failing that you can ask for a paper listing of PROGINIT.MAC instead. Some dealers may be able to provide other formats.

The Manual: The eight page manual covers the installation of the programmer, and the use of CPROG and PROG. Also a brief section is included on how Microsoft’s M80/L80 combination can be used to create ROMable programs, There is no description of the internal circuitry of the programmer nor is there any information on how it should be driven by any program other than that supplied. (But see PROGINIT.MAC below.)

Using the Software

The configuration program CPROG allows the user to change two parameters within PROG. The first is the base address of the PIO that is driving the programmer, and the second is the default EPROM type that PROG assumes when it is invoked. The latter option saves the user the irritation of having to use the -Change EPROM type” option every time that PROG is used.

The main program PROG drives the programmer, and transfers data in both directions between disk files and a EPROMs via a buffer that it maintains in memory. When invoked it puts up a heading together with a menu from which the following options can be selected:

0 – Return to CP/M.

1 – Change EPROM type. This brings up a sub-menu offering the choice of 2716, 2732, 2732A, 2764, 27128, and 27256.

2 —- Read an EPROM into the buffer. This prompts for an EPROM to be inserted into the socket, and then reads it into the buffer.

3 – Read a disk file into the buffer. (A prompt for a file name will appear.)

This is an OCR’d version of the scanned page and likely contains recognition errors.

Page 32 of 51