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+## MODBUS Registers
+
+### Input Registers
+
+|Value|Register|
+|---|---|
+|CO2  | 30010|
+|SHT4x  | 30011|
+|RH SHT4x  | 30012|
+|T SCD4x  | 30013|
+|RH SCD4x  | 30014|
+|T SHT4x SIGNED  | 30015|
+|T SCD4x SIGNED  | 30016|
+
+### Holding Registers
+
+|Value|Register|
+|---|---|
+|LED ON  | 40001|
+|CO2 ALERT LIMIT1  | 40002|
+|CO2 ALERT LIMIT2  | 40003|
+|MODBUS ADDR  | 40004|
+
+### Device Information Registers
+
+|Value|Register|
+|---|---|
+|VENDOR NAME  | 30010|
+|PRODUCT CODE  | 30011|
+|REVISION  | 30012|
+|PRODUCT NAME  | 30013|
+|SERIAL NUMBER  | 30014|