In the example below, the flow control on the minicomputer works as follows:
Channel 1 2
3
Mini- 4
Computer 5
6
7
8
Data
A.
Flow Control
B.off
C.Flow Control on
Data
D.
Mux
Link
mux process data to the link
mux buffers full
mux buffers empty
mux processes data to the link
A.Data volume from the mini for any particular channel is appropriate for the mux to process and transfer on to the link.
B.Data overwhelms a channel's mux buffer and the mux sends a stop data Flow Control (OFF) signal to the mini stopping data output.
C.The mux buffer sufficiently enpties to allow additional data transfer, so the mux sends a start data Flow Control (ON) signal to the mini.
D.Data from the mini again flows through the channel.