(b)CPU (Central Processing Unit)
The Central Processing Unit is divided into two sections: common control and speech path.
Common control: This section consists of a microcomputer and associated other circuits. It controls receiving dial data from stations, opening and closing of speech path, controlling of signal, paging and BGM switches in accordance with the exchange program.
Speech path: This section consists of a voice switching circuit, signal generator, link busy signal circuit, BGM amp and the paging amp. It is controlled by the common control section.
| dial data input |
| |
| common |
| |
control output | control | remote | |
control | |||
| circuit | ||
|
| ||
| link control |
| |
|
| paging | |
| link |
| |
speech signal in | (voice switching | speech signal out |
circuit)
signal
generator
BGM
link busy
4