unclear use of a function in spi tutorial (c synta

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i understand in spi eeprom tutorial except use of spi_transfer(volatile char data) function:

spi_transfer((char)[/b](eeprom_address>>8));   //send msbyte address first
 spi_transfer((char)(eeprom_address));  

why (char) put there?  i have never seen syntax before.

in tutorial address 16bit number. spi_transfer() function expects 8bit numbers. char 8 bits wide. first call transfers high byte, second call low byte. char-cast throws away bits above 1-byte boundary. that's why in first call high byte shifted 8 bits right, "ordinary bytes" live, upper part tossed away , remaining data gets sent.


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