Watec WAT-910BD, Руководство по оборудованию

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WAT-910BD H/W MANUAL
//----------------------------------------------------------------------
// FUNCTION: SPI_WRITE_3W
//
// SPI WRITE SEND_BUFF[0...(W_Byte-1)]
// In case of Indirect access, it must W_Adr = 0x36 and W_Byte = 8.
// In case of 3Wire, it need change GPIO(MISO/MOSI) direction
// input/output.
//----------------------------------------------------------------------
unsigned char SPI_WRITE_3W(unsigned char W_Adr, unsigned char W_Byte)
{
int i ;
int j ;
int WriteCMD ;
unsigned char SendBit ;
// make SPI WRITE COMMAND
WriteCMD = (int)W_Adr << 1 ;
SEND_BUFF[0] = (unsigned char)WriteCMD ; // lower 8bit
SEND_BUFF[1] = (unsigned char)(WriteCMD >> 8) ; // higher 8bit
i = 0 ; // Byte Counter
// initialize SPI bus
p3_5 = 1 ; // SS = H
p3_4 = 1 ; // SCLK = H
wait_nop() ;
// SPI WRITE COMMAND send start
pd3_3 = 1; // set port direction MOSI(output)
p3_3 = 1 ; // MOSI = H
p3_5 = 0 ; // SS = L
while( i < W_Byte ){ // W_Byte must 8 in INDIRECT ACCESS
j = 1 ; // Bit Mask
while(j < 0xFF){ // 8bit send
SendBit = SEND_BUFF[i] & j ? 1 : 0 ; // bit test
j = j << 1 ; // j *= 2 ;
p3_4 = 0 ; // SCLK = L
p3_3 = SendBit ; // output LSB first bit data on MOSI
wait_nop() ;
p3_4 = 1 ; // SCLK = H(latch)
}
i ++ ; // Next byte
wait_nop() ;
}
p3_5 = 1 ; // SS = H(END)
pd3_3 = 0; // set port direction MISO(input)
wait_ms(1) ;
// CTL-COMMAND execution is done ?
READ_BUFF[0] = 0xAA ; // initialize
while( READ_BUFF[0] == 0xAA ){ // 0xAA means busy
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