Printer pacing and Flow Control
The example below shows how Pacing and Flow Control work on a printer.
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Computer | 1 |
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| Printer | |
A. |
| Print Data |
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| Pace |
| Data |
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B. |
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| Print Buffer | |||
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| off |
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| Flow Control |
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| Full |
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C. |
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| Flow Control |
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D. |
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off |
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| Pace | Printer | ||
E. |
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| on | Ready | ||
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F. |
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| Flow Control |
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G. | Flow Control |
| on |
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on |
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| Print Data |
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H. |
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A.Print data volume from the mini is appropriate for the printer to process and print it.
B.The printer cannot handle any more data due to its buffers being full and it issues a Pace OFF signal to the mux.
C.The remote mux sends a Flow Control OFF signal to the other mux and uses its buffer to store any pending print data.
D.The host mux sends a Flow Control OFF signal to the mini and uses its buffer to store any pending print data.
E,F,G. The printer buffer empties and is ready for more print data, so it issues a Pace ON signal which, in turn, causes a Flow Control ON signal through to the mini.
H. Print data from the mini resumes.
