Changes

The original [[Schneider RS232 Interface]] was released around 1985. Two years later, in 1987, a software-compatible clone was released as DIY schematic in a german German book ([[Maschinenspracheprogramme und Hardware-Erweiterungen für Schneider CPC's|link]]). Even later, around 1996, a copy of that DIY schematic also circulated in the internet ([[Tim Riemann's RS232 interface|link]]). The DIY port address, timings and handshake signals are exactly the same as in the original Schneider version - except that DCD (Data Carrier Detect) isn't implemented in the DIY version.