Anders ausgedrückt, ich wollte nun so verfahren :
1 | Xuint8 sd_send_cmd(Xuint8 Command, Xuint16 ParameterX, Xuint16 ParameterY)
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2 | {
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3 | Xuint8 response;
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4 | XIo_Out32((SPI_BASE_ADDRESS)+ SPI_Slave_Select_Register, CS_LOW); // CS -> LOW
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5 | delay(50); // wait some CLKs for stable CLK Signal
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6 |
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7 | spi_send_byte(0x40 | Command); //send the command
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8 |
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9 | spi_send_byte((Xuint8) (ParameterX >> 8)); //send the MSB of ParamX
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10 |
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11 | spi_send_byte((Xuint8) (ParameterX)); //send the LSB of ParamX
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12 |
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13 | spi_send_byte((Xuint8) (ParameterY >> 8)); //send the MSB of ParamY
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14 |
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15 | spi_send_byte((Xuint8) (ParameterY)); //send the LSB of ParamY
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16 |
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17 | switch(Command)
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18 | {
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19 | case CMD8:
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20 | //when sending the IF cond (CMD8) we must always send
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21 | //the correct CRC
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22 | spi_send_byte(0x87);
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23 | break;
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24 |
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25 | case CMD0:
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26 | //CMD0 = 0x95 CRC
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27 | spi_send_byte(0x95);
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28 | break;
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29 |
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30 | default:
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31 | //for all other commands, CRC is ignored in SPI mode.
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32 | spi_send_byte(0xFF);
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33 | break;
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34 | }
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35 |
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36 | response = spi_read_byte(); // read the SD response
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37 |
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38 |
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39 | XIo_Out32((SPI_BASE_ADDRESS)+ SPI_Slave_Select_Register, CS_HIGH); // CS -> HIGH
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40 |
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41 | return response;
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42 | }
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