The program would not normally reside in memory (unless, as in the
author’s case, on an EPROM board that can be paged in or out of the
INMC80 No. 4).
Normally, it would be loaded from disc or tape.
The listing was written using the CP/M Editor ‘ED’ for assembly by Macro 80,
because program development is easier with these more powerful utilities. It should
be easy to alter it to suit ZEAP. The main changes required are:–
Leave out the colons after labels;
Remove the assembler directives END,.Z80,ASEG,.PHASE and .DEPHASE;
Substitute a suitable memory ORG address;
Substitute " in place of ' in compare instructions.
If you have ‘ED’ or any other editor with MACRO find/substitute commands it
should be very easy to make the changes needed to the Source code. Otherwise,
there should be few problems. The PIO
ports are defined for the I/O board (using
ports 14 and 15). These can be changed in the equates section of the listing.
The program is written so that the user is reminded, by means of messages on
the screen, to take suitable precautions when handling chips. User input is in the
form of single key replies to prompts on the screen. All entries are echoed on the
screen and the user may change them. The various routines are listed in the form of
When the program is executed, the title is placed on the left side of the top
(unscrolled) line of the screen, and warnings about chip handling appear for a couple
of seconds. The program then prompts the operator to press key ‘C’ when he is
ready to continue. Whilst waiting for a response, the program display a message
warning the operator to switch off when inserting or removing chips. When key C is
pressed a prompt asks for the type of EPROM to be handled – key A should be
pressed for 2708s, key B for 2516/2716s.
When this entry has been made, the user is asked to verify it by a ‘Y’ or ‘N’
response. If ‘N’ is entered the program repeats the request for the EPROM type,
while on receipt of ‘Y’ the type selected is displayed on the right hand side of the top
line, and remains there until changed. In addition the value stored in the program
workspace at the location ROMFLG is set to 04H for 1K EPROMs, or 08H for 2K
The ‘Menu’ for the five routines is then displayed, together with a list of the keys
needed to access the routines. Once a routine has been selected and verified, it is