The invention discloses a hard real-time cascading multi-node synchronous sampling and
data transmission method. The method comprises the following steps: 1) dividing a cascading
system into four
layers; 2) determining a sampling interval Ts of the cascading
system, dividing a physical channel into two logical channels: a real-time logical channel and a non-real-time logical channel; 3) orderly constructing devices in a second layer, a third layer and a fourth layer for synchronous sampling, synchronous transmission and
link management in the cascading
system; 4) computing a channel retardation of each layer; 5) reconstructing a local synchronous
signal of a data combining and transferring device of the third layer, and a local synchronous
signal of a
data acquisition and control terminal of the fourth layer; 6) controlling
data transmission by using sampling period Ts as
rhythm. The extra time
delay produced by physical link length and
software protocol stack among a plurality of multi-stage cascaded acquisition control nodes in different physical distribution is solved, and the hard real-
time transfer capability is provided for the key service data, the synchronous precision and real time property are high, the channel construction cost and the construction
workload are low, and the good application prospect is realized.