Modbus (1 июн 1970 г. – 1 дек 1974 г.)
Описание:
In the early 1970’s communications between PLCs started to develop. Modbus was introduced as the first industrial communications network. This communication network was based on a Master/Slave architecture using messaging to communicate between Modbus nodes. Its original interface ran on RS-232 but later implementations used RS-485 to allow for quicker communications that could run longer distances. However, the lack of standardization and changing technology made PLC communications a nightmare.
Добавлено на ленту времени:
Дата:
1 июн 1970 г.
1 дек 1974 г.
~ 4 years and 6 months