Technical information

CSI to SPI Peripheral Communication in V850ES Microcontrollers
Figure 9. Read and Write Cycles From the Master to the DS1722 Temperature Sensor
Write from Master to DS1722
Read from DS1722 to Master
Table 4 lists the addresses accepted by the DS1722 sensor and the action performed on those addresses.
Table 4. Addresses Accepted by the DS1722 Temperature Sensor
SDI first byte
(Address)
Second Byte Direction
Second
Byte SDI
Second
Byte SDO
Data Transferred
00H Read from DS1722 Ignored Driven Configuration register Read
01H Read from DS1722 Ignored Driven Temperature LSB (D15 to D8) read
02H Read from DS1722 Ignored Driven Temperature MSB (D7 to D0) read
80H Write to DS1722 Accepted High-Z Configuration register write
Read transfers from the DS1722 temperature sensor allow multiple registers to be read. The first written
byte specifies the address, and the first read byte will be the data from that address. If further bytes are
read, the address will be incremented once for each byte read. For example, if address 00H is specified,
the first read byte will be the Configuration register, the second read byte will be temperature LSB, and
third read byte will be temperature MSB.
To read all 16 bits of temperature data, the master would write the address 01H, and then read two bytes
(temperature LSB and temperature MSB).
The temperature is a 16-bit signed value, with a sign bit (D15), eleven bits of temperature data (D14 to
D4), and four zero bits (D3 to D0). The eleven bits of temperature data is in degrees Centigrade, with the
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