PMD 85

Specifications

• MHB8080A 2.048MHz CPU
• 48 KiB RAM
• 4 KiB ROM
• System monitor
• Tape utilities
• TV output or RGB component video
• 288×256 resolution
• 4-level attribute, selectable per 6-pixel-wide stripes
• Tape recorder interface
• IRPS interface
• Module interface. A ROM module with the BASIC programming language was a standard part of the computer, but there were more ROM modules containing Pascal, Assembler, LOGO etc. A programmer was also available.
• IMS-2 interface based on MHB8255A
• Two 8-bit parallel buses supporting handshaking
• Application connector

  Variants

• The PMD 85-0, a prototype produced by Tesla Piešťany, was originally in a white-coloured case and later in some other colours. It is quite rare today.
• The PMD 85, produced by Tesla Piešťany since 1985, was known as the PMD 85 or PMD 85-1. It was made with a dark gray case, and was known for its keyboards with extremely tough keys. Alphanumeric keys were evaluated at the moment of a key release.
• The PMD 85-2, produced by Tesla Piešťany since 1986, introduced some improvements in BASIC, some in input routines, a more ergonomic keyboard and also terminal mode. Some of the changes caused it to be not completely backward compatible.
• The PMD 85-2A, produced by Tesla Bratislava since 1987, used 64 Kib RAM chips instead of 48 Kib, leading to less overheating of the memory chips, resulting in more memory available for BASIC, but was otherwise compatible with PMD 85-2.
• The PMD 85-3, produced by Tesla Bratislava since 1988, added colour TV output. Character encoding included all Czech and Slovak characters, and a Cyrillic version was also produced. System memory was enlarged to 8 KiB and monitor included routines for communication with PMD 32 floppy disk assembly, a ROM integrity test and also "PMD 85-2 compatibility mode" by relocation.