Archive for the ‘Olivetti family’ Category

Repairing a defective Olivetti M21

February 23rd, 2014 4 comments
Olivetti M21


Olivetti S.p.A. is an Italian manufacturer of computers, tablets, smartphones, printers and other business products such as calculators and fax machines. Headquartered in Ivrea, province of Turin, the company has been part of the Telecom Italia Group since 2003.

The primacy of the first PC can be assigned to Olivetti thanks to Programma 101, which was produced in 1964 and had a big success in the U.S. market.

Olivetti’s first modern personal computer, the Olivetti M20, featuring a Zilog Z8000 CPU, was released in 1982. In 1983 Olivetti introduced the M24 and in 1984 the M21 (the first and last of transportable of Olivetti), a clone of the IBM PC using DOS and the Intel 8086 processor (at 8 MHz) instead of the Intel 8088 used by IBM (at 4.77 MHz).

The M24 was sold in North America as the AT&T 6300. Olivetti also manufactured the AT&T 6300 Plus, which could run both DOS and Unix.

The comparison (before / after):

Repairing & things before of the Cleaning:


  • Mirror image.
  • Sometimes garbled image with using the ISA Bus.

Replaced parts:

  • Replaced a 74LS245N on the motherboard side.
  • Replaced a 75LS244N on ISA expansion Module.
  • Removed the battery for the Realtime Clock.


  • Bios v1.36 to v1.43 (latest).

source: wikipedia

Olivetti Diskette 5.25 ETS

January 8th, 2012 1 comment
Olivetti Diskette 5.25 ETS


I found during my moving house a few boxes of unopened Floppy Disk 5.25 of Olivetti.

Olivetti Prodest PC128

July 1st, 2011 No comments
Olivetti Prodest PC128


The Prodest PC-128 was a rebadged and slightly redesigned version of the French Thomson MO6, apart from case design touching up, technical features was the same as the MO6.

The Prodest PC-128 has two versions of BASIC on ROM both made by Microsoft. Almost all memory (101 KB) was accessible with BASIC thanks to a transparent 16 KB bank switching mechanism. An optional 3.5″ floppy disk drive (640 KB) was available. This machine seems having been sold in very small quantity in Italy.