A Brief History of the MZ-2500

A Brief History of the MZ-2500

written by Maurice Hawes / SUC/UK
Source: SUC-magazine November 1999, Volume 19 Number 3, p. 21

This was the only Sharp MZ-machine that had 3.5“ disk drives as standard. We have no brochures, but we do have a working machine with 2 internal 3.5“ drives, 2 external 5.25“ drives, a 3.5″ master of Disk BASIC MZ-6Z002, and a few pages copied from a draft Manual which include freehand drawings of the front and rear panels of the machine; the front panel incorporates a small drop-down control pad which includes a 3-way MODE switch for running the machine in MZ-2500, MZ-2000 / 2200, or MZ-80B mode:

Modes of the MZ-2500

We checked that, using the MODE switch, the MZ-2500 can indeed run software from the MZ-2000 or the MZ-80B. We also found that in MZ-2500 mode we could redefine the 5.25“ drives as ‘MZ-80B‘ and thus transfer the ‘B‘ version of Tanswell‘s Disassembler to the MZ-2500. We were then able to ‘tweak‘ that Disassembler to run on the MZ-2500, and use it to sort out the BASIC and unravel the RAM / ROM memory map ( see Vol. 18 Nos. 1 – 2 ); in a nutshell it uses sophisticated bank-switching to handle a maximum of 384KB, and with this amount of memory, BASIC announces ‘234655 Bytes Free‘ !

There is also a version of ‘Personal CP/M‘ ( PCP/M ) for the MZ-2500. So far we have been unable to obtain a copy of this system; but we do have its Manual ( in Japanese ! ) and this contains enough English words to deduce that MZ-2500 PCP/M is similar to MZ-800 PCP/M but more extensive, as it includes the extra files TRANS.COM, SPOOL.COM, MEMDISK.COM and WM.COM – the last being a stand-alone wordprocessor called WORDMASTER ( v2.03 ).

BASIC 6Z002 puts date-stamps on its files; the earliest file on the MZ-6Z002 master disk is dated 2nd October 1985, but the most important system files are dated 6 – 7th February 1986.