Writing a Parallel Communication Driver
D–7
Publication 17706.5.20 - June 1997
To receive the upper nibble, the host:
1. Sets pin 14 (Auto Feed) to 1.
2. Reads the data.
3. Sets pin 1 (Strobe) to 0 then 1.
At this point the KFC15/KFCD15 sets pin 11 (Busy) to 0. This
completes the transmission of one byte. If there is more data to send,
the KFC15/KFCD15:
"
Sets pin 15 (Error) and pin 12 (P. End) to 0.
and the host:
"
Sets pin 14 (Auto Feed) to 0, then repeats its receive procedure.
If there is no more to send, the KFC15/KFCD15:
1. Sets pin 15 (Error) and pin 12 (P. End) to 1.
2. Sets pin 10 (Acknowledge) to 1.
and the host sets pin 17 (Select Input) to 1.