EASY-TO-USE PRINTER LINK
KEMPSTON MICROELECTRONICS has produced a Centronics printer interface which plugs on the back of the Spectrum. There is nothing spectacular in the box as it is an 8255 chip used as a port to access the printer cable.
The printer cable is a full 35-way type and is about one metre long. The plug at the end which fits on the printer seemed a little too thick to put the securing clips around but it was a tight fit in the socket.
All the hard work is done in 650 bytes of machine code stored above RAMTOP; a different program is provided for each computer. That may seem a great deal but the accompanying Basic program allows you to specify a number of options on the printer. Once those options are set, the program will save the machine code only to allow you to use all the rest of the RAM yourself.
Line length, changing the character codes for individual characters, special features such as the line feed and carriage return, can be set in software. All those commands affect only LPRINT and LLIST as COPY is ignored.
Any of the options can be ignored by pressing ENTER in response to the question. In that way a printing routine can be personalised and if, say, the line length is limited to 32, LLIST would produce a duplicate of that listed on the screen.
Hilderbay, the company which produced the software, must be congratulated on providing a fine, easy-to-use piece of software.
The only way to COPY a screen suggested in the instructions is to use the Basic Point command in a loop to assemble the required graphic bytes to put out to the printer. That is useful but slow and the routine applies only to Epson printers. Looking through the printer manual is the only answer if you do not have one of those.
A machine code program for at least two of the popular printers to simulate, if not use the COPY command, would have been useful. That seems preferable to the LPRINT, is it allows you control of the printer with as much ease as possible.
The printer interface costs £45 and is available from Kempston Microelectronics, 180a Bedford Road, Kempston, Bedford MK42 8BL.