
A96G166/A96A166/A96S166 User’s manual
22. Development tools
233
22.5.1
Two-pin external interface
Basic transmission packet
10-bit packet transmission using two-pin interface.
1-packet consists of 8-bit data, 1-bit parity and 1-bit acknowledge.
Parity is even of
‘
1
’
for 8-bit data in transmitter.
Receiver generates acknowledge bit as
‘
0
’
when transmission for 8-bit data and its parity
has no error.
When transmitter has no acknowledge (Acknowledge bit is
‘
1
’
at tenth clock), error process
is executed in transmitter.
When acknowledge error is generated, host PC makes stop condition and transmits
command which has error again.
Background debugger command is composed of a bundle of packet.
Start condition and stop condition notify the start and the stop of background debugger
command respectively.
Figure 137. 10-bit Transmission Packet