Commodore cassette interface - THE alternative

Commodore cassette interface Necessity being the mother of invention this circuit was destined to be designed. The "necessity" here is Commodore"s insistence that the VIC 20 and C64 computers can only be used with a special cassette recorder supplied by ... Commodore. One of our designers baulked at the idea of buying a cassette recorder only for his computer when he already had a perfectly good audio recorder. Some kindly soul directed his outraged energy towards the nearest soldering iron and so was born THE Commodore cassette interface by Elektor. As in many home computers, the data out- put by the VIC 20 and C64 via the cassette interface is in the form of a square wave signal with an amplitude of 5 Vpp. The information input to the com- puter has the same form. The cassette connector also contains a so-called "sense input" that enables the computer to check if the recorder"s PLAY button is pressed. The Commodore will only activate its motor output if this is the case. The com...