6100 BSC Programming Manual

Writing Applications that Use 6100 BSC
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| |
| |
| Local Station (Prim.) Remote Station (Sec.) |
| |
| / ENQ ---------> |
| | \ |
| | <--------- ENQ | WRITE |
| | | request |
| | ENQ ---------> | (completes with |
| WRITE | / status 166--ENQ) |
| request | \ |
| | <-------- ACK 0 | READ |
| | | request |
| | msg ---------> | (yields to primary)|
| | / |
| | \ |
| \ <-------- ACK 1 | READ |
| / | request |
| WRITE | msg ---------> | |
| request | / |
| | \ |
| \ <-------- ACK 0 | READ request |
| |
| |
| |
| The underscore shows the information applications |
| supply and receive. In each case, the information |
| resides in the text field of the request/response |
| buffer (see Figure 3-9). Items not underscored--for |
| example, most control sequences--are supplied and |
| received by the protocol, not by the application. |
| |
| |
| |
| |
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Figure 3-4. Line Bid, Contention and Resolution
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