智能烘箱温度控制器设计-英文翻译(7)

measurement. So in actual temperature measurement applications, should avoid as far as possible is placed near the MAX6675 heating device or element, because it will cause the error of the cold end. As shown in figure 2-5 MAX6675 connection.

Figure 2-5 MAX6675 connection

SPI interface: MAX6675 with a standard SPI serial peripheral interface with MCU, and MAX6675 only as from the device. Output MAX6675S0 temperature data format, as shown in the table 2-6 MAX6675SPI interface timing as shown in figure 2-7. MAX6675 from SPI serial interface data output process is as follows: MCU make the CS low and provides the clock signal to SCK, by SO read the measured results. CS is low will stop any conversion process; CS is high will be starting a new conversion process. A complete serial interface reads need 16 clock cycles, read on the falling edge of the clock output of 16 bits, bit 1 and 15 is a false flag, and the total of 0; 14th to third in the MSB to sequential LSB of transformation temperature; 2nd at the bottom, at ordinary times is higher when the thermocouple input open open thermocouple detection circuit implemented by MAX6675 fully, for open thermocouple detector operation, T - must be grounded, and can