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5.1. Issuing a Measurement Command

The measurement commands instruct the TH06 to perform one of two possible measurements; Relative Humidity

or Temperature. The procedure to issue any one of these commands is identical. While the measurement is in

progress, the option of either clock stretching (Hold Master Mode) or Not Acknowledging read requests (No Hold

Master Mode) is available to indicate to the master that the measurement is in progress; the chosen command

code determines which mode is used.

Optionally, a checksum byte can be returned from the slave for use in checking for transmission errors. The

checksum byte will follow the least significant measurement byte if it is acknowledged by the master. The

checksum byte is not returned if the master “not acknowledges” the least significant measurement byte. The

The checksum byte is optional after initiating an RH or temperature measurement with commands 0xE5, 0xF5,

0xE3, and 0xF3. For all other commands, the checksum byte is not supported.

Master

Slave

Sequence to perform a measurement and read back result (Hold Master Mode)

S

Slave

Address

W

A

Measure

Cmd

A

Sr

Slave

Address

R

A

Clock stretch

during

measurement

MS Byte

A

LS Byte

NA

P

A

Checksum

NA

P