Hitachi RAS-E08H2A Service Manual page 41

Outdoor microcomputer Pin 48
Pin 51
Indoor microcomputer Pin 50
Pin 49
35V DC line
Fig. 2-2 Voltages Waveforms of Indoor / Outdoor Microcomputers (Outdoor to Indoor Communications)
Outdoor microcomputer Pin 48
Pin 51
Indoor microcomputer Pin 50
Pin 49
35V DC line
Fig. 2-3 Voltages Waveforms of Indoor / Outdoor Microcomputers (Indoor to Outdoor Communications)
48
5
50
49
100ms.
Leader
48
5
50
49
4.95ms.
Transmit/receive
switching time
33ms.
1 frame
33ms.
1 frame
– 39 –
5V
0V
5V
0V
5V
0V
5V
0V
35V
0V
5V
0V
5V
0V
5V
0V
35V