Functions
Function 1 and 2: read N bits
◗function 1: read output or internal bits;
◗function 4: read input bits.
The number of bits must be less than or equal to the bit field size (see memory board).
JBUS protocol (continued)
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| slave address |
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| address of | number of bits | CRC 16 | ||
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| first bit | ||||||
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| MSB LSB |
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| 1 byte |
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| 1 byte |
| 2 bytes | 2 bytes | 2 bytes | |||
response |
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slave address | 1 or 2 | number of | first | last | CRC 16 |
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1 byte | 1 byte | 1 byte |
| ✷ bytes | 2 bytes |
byte detail: |
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last bit transmitted | first bit transmitted |
Unused bits are set to zero
example
Reading bits at location 404 to 411 of slave at address 20H (charger signals)
request:
20 01 0404 0E 66 FE
response:
20 | 01 | 02 | 10101001 | 00101110 | FB B7 |
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| 40B |
| 404 411 |
| 40C | ||||||||
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6739389EN/FB - Page 9
