Linking to Other Systems with FETCH/WRITE
a) Structure of WRITE Frames
The meaning and values of parameters shown without values in the following table can be found in the section “Parameter Values“.
WRITE request frame
0 | System ID | =”S” |
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1 |
| =”5” |
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2 | Length of header | =16d. |
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3 | ID OP code | =01 |
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4 | Length OP code | =03 |
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5 | OP code | =03 |
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6 | ORG field | =03 |
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7 | Length ORG field | =08 |
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8 | ORG ID |
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9 | DBNR |
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A | Start address | High Byte |
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B |
| Low Byte |
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C | Length | High Byte |
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D |
| Low Byte |
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E | Empty field | =FFh. |
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F | Length empty field | =02 |
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| Data up to 64 K |
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WRITE acknowledgment frame
0 | System ID | =”S” |
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1 |
| =”5” |
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2 | Length of header | =16d. |
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3 | ID OP code | =01 |
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4 | Length OP code | =03 |
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5 | OP code | =04 |
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6 | Ack field | =0Fh |
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7 | Length ack field | =03 |
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8 | Error field | =No |
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9 | Empty field | =FFh |
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A | Length empty field | =07 |
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B |
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C |
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Dfree
E F
244 | SIMATIC NET NCM S7 for Industrial Ethernet |
Release 6/2003 |
