The converter described is controlled by a small I/O unit that has an adequate number of inputs and outputs. It may be built on a small piece of prototyping board and connected to the I/O ward via Kl. The 12 V supply and the clock DSC = 14.318 MHz) which, divided by 16, is: used to clock the converter, are derived from the I/O card. The clock may also be driven nom a PC, but that on the I/O card is independent of the computer.
How the converter is operated is shown in the BASIC program. except for one action. The EOC output (which goes high at the end of a conversion) needs a minimum of 0 clock pulses and a maximum of eight clock pulses plus 2 Us after the leading edge of the start pulse to go low. This means that with compiled software or machine language routines EOC must be checked in the correct manner (that is looking online 200 whether EOC is high).