Watec WAT-910BD, Руководство по оборудованию

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WAT-910BD H/W MANUAL
SPI_READ_3W(0x3B, 1) ; // ST CODE read
wait_ms(1) ; // 1mS wait
}
if( READ_BUFF[0] == 0x55){ // 0x55 means EXEC.NORMALLY
return TRUE ;
}else{
return FALSE ;
}
}
//----------------------------------------------------------------------
// FUNCTION: SPI_READ_3W
//
// SPI WRITE READ_BUFF[0...(R_Byte-1)]
// In case of 3Wire, it need change GPIO(MISO/MOSI) direction
// input/output.
//----------------------------------------------------------------------
unsigned char SPI_READ_3W(unsigned char R_Adr, unsigned char R_Byte)
{
int ReadCMD ; // SPI READ COMMAND
int i ; // counter
int j ;
unsigned char SendBit ;
// make SPI READ COMMAND
ReadCMD = ((int)R_Adr << 1) + 1 ;
SEND_BUFF[0] = (unsigned char)ReadCMD ; // lower 8bit
SEND_BUFF[1] = (unsigned char)(ReadCMD >> 8) ; // higher 8bit
i = 0 ; // Byte Counter
// initialize SPI bus
p3_5 = 1 ; // SS = H
p3_4 = 1 ; // SCLK = H
wait_nop() ;
// SPI READ COMMAND send start
pd3_3 = 1; // set port direction MOSI(output)
p3_3 = 1 ; // MOSI = H
p3_5 = 0 ; // SS = L
wait_nop() ;
while( i < 2 ){ // 2 byte loop
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)
}
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