Datasheet

Seite 15
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SERIAL DIGITAL INTERFACE
Com-
mand
(HEX)
Data Command Remarks Processing
time
System clock
2MHz /
EEPROM-
Progr. Steps
80 .. 8F 2 Byte WRITE_RAM0 Write data to RAM address 00 .. 0F
50µs
90 .. 9F 2 Byte WRITE_RAM1 Write data to RAM address 10 .. 1F
50µs
A0 .. AF 2 Byte WRITE_EEP0 Write data to EEPROM address 00 .. 0F 12.5ms / 1
B0 .. BF 2 Byte WRITE_EEP1 Write data to EEPROM address 10 .. 1F 12.5ms / 1
C0 COPY_EEP2RAM Copy Contents of EEPROM to RAM
Restores EEPROM Configuration in RAM
130µs
C3 COPY_RAM2EEP Copy Contents of RAM to EEPROM
Stores RAM Configuration to EEPROM
(signature is copied without check!!!)
400ms / 32
C8 GET_EEP_SIGN Calculates EEPROM Signature and output to SIF
Output Register
150µs
C9 GEN_EEP_SIGN GET_EEP_SIGN + write the Signature to EEPROM
address 0x1D
12.6ms / 1
CA GET_RAM_SIGN Calculates RAM Signature and output to SIF Output
Register
150µs
CB GEN_RAM_SIGN GET_RAM_SIGN + write the Signature to RAM
address 0x1D
150µs
CC CLEAR_EEP Clear EEPROM
Sets complete EEPROM to 0x0000
12.5ms / 1
CF ROM_VERSION Read ROM version and write it to SIF Output Register
Usually followed by Read operation
50µs
All “D*”-Commands: used for calibration process, write raw conversion result to SIF Output Registers, do not effect to
analog output
D0 START_AD_P Start cyclic A/D-conversion at channel Humidity P
D1 START_AD_T1 Start cyclic A/D-conversion at channel Temperature
T1
D2 START_AD_T2 Start cyclic A/D-conversion at channel Temperature
T2
D4 START_AD_PAZ Start cyclic A/D-conversion at channel Auto-Zero
Humidity PAZ
D5 START_AD_TAZ1 Start cyclic A/D-conversion at channel Auto-Zero
Temperature TAZ1
D6 START_AD_TAZ2 Start cyclic A/D-conversion at channel Auto-Zero
Temperature TAZ2
D8 START_AD_P_AZ Start cyclic A/D-conversion at channel Humidity P incl.
Auto-Zero-Correction
D9 START_AD_T1_AZ Start cyclic A/D-conversion at channel Temperature
T1 incl. Auto-Zero-Correction
DA START_AD_T2_AZ Start cyclic A/D-conversion at channel Temperature
T2 incl. Auto-Zero-Correction
DB START_AD_CMV_AZ Start cyclic A/D-conversion at channel Common Mode
Voltage CMV
incl. Auto-Zero-Correction
50µs
+
AD-
conversion
time
Table 3: Additional command set for serial digital interface
Note: These commands are only available in CM.
CM is set by command START_CM (0x72
hex
) as first command after power on.