This is data to which
PC side
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| GET command |
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| 02 (hex) | 2 Byte |
| 3 Byte |
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| 03 (hex) |
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| STX |
| GET command |
| Data |
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| Check Sum |
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| 02 (hex) |
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| *Byte |
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| 03 (hex) | ||
| A detailed example will be given below. |
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| Example: The Check Sum value that is added when the GET command GAA returned the following |
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| Data group (ASCII) |
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| GET command |
| Data (6 Byte) |
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| Check Sum |
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| GAA |
| 100128 |
| xx (before calculation) |
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| The data group is put in to binary code one |
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| 47 | 41 | 41 |
| 31 30 30 | 31 32 | 38 |
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| character at a time and displayed (only the |
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| last two digits are displayed) |
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When these values are added the result is 1F8 (hex)
As the data format, F5 is converted to ASCII code and sent.
The following data is output from the plasma display side.
STX | GET command | Data | Check Sum | ETX |
02 (hex) | GAA | 100 (missing data) 28 | F5 | 03 (hex) |
Note: The returned data group will be in capital letters. Please keep this in mind when introducing it into the binary display.
Example of Check Sum applicationsExample 1: when the data is missing one Byte
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| Check Sum | ETX | |||
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| GAA |
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| 100 (missing data) 28 |
| F5 |
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| 02 (hex) |
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| 47 | 41 | 41 | 31 | 30 | 30 | 32 | 38 |
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The data group is calculated according to the rules by a PC application and when these values are added the result is 1C4 (hex).
Here, the check sum [F5 (hex)] and the calculated [C4 (hex)] do not match.
Since they do not match, the PC application sends the GET command again and gets the data again.
Example 2: when one Byte of data is unreadable
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| STX |
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| GET command |
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| Data (6 Byte) |
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| Check Sum | ETX | |||
| 02 (hex) |
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| 100328 |
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| F5 | 03 (hex) | ||
| 47 | 41 | 41 | 31 | 30 | 33 | 30 | 32 | 38 |
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The data group is calculated according to the rules by a PC application and when these values are added the result is 1F7 (hex).
Here, the check sum [F5 (hex)] and the calculated [F7 (hex)] do not match.
Since they do not match, the PC application sends the GET command again and gets the data again.
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