RS 232 interface - serial transfer via the universal 1/0 bus

elektor electronics september 1985 J Steeman The name RS232 represents a number of standard conventions that aim to ensure the correct transfer of data irrespective of the individual characteristics of a computer. Most computers have a serial input & output port for connecting a printer, a DCE (Data Circuit Terminating Equipment), or even another computer. To marry the two, we have designed an RS232 card, which is intended for the universal 1/0 bus featured in the May 1985 issue of elektor elec- tronics. There is a choice of TTL or RS232 line levels. RS232 interface serial transfer via the universal 1/0 bus Parallel transfer of data, whereby all bits of a character are transferred simultaneously, is normally used where the distance between the computer and the peripheral equipment is relatively short. This means that a wire connection is required for each of these bits. This is a very reliable method of transfer, but if longer distances are involved, it becomes prohibitively expen...