anchor.diff:  LC_TEST,Testing,sparse_double,PD1554,HID NA,NA,sparse,float64,,1,-9999999,Sparse Double,,,,,,,,,,,,,,
   LC_TEST,Testing,sparse_int,PD1555,HID NA,NA,sparse,int64,,1,65535,Sparse Integer,,,,,,,,,,,,,,
   BASE,,lat,PD1556,HID NA,NA,sparse,float64,,degree_north,-9999,Latitude,,FALSE,,,,,,,,,,,,
  -BASE,,lon,PD1557,HID NA,NA,sparse,float64,,degree_east,-9999,Longitude,,FALSE,,,,,,,,,,,,+BASE,,lon,PD1557,HID NA,NA,sparse,float64,,degree_east,-9999,Longitude,,FALSE,,,,,,,,,,,,
  
positive.code: BASE,,counts,PD14,counts_quantity_uint64_counts,0,quantity,uint64,,counts,0,,0,,,,,,,,,,,,,
  BASE,PARAD,checksum,PD15,checksum_quantity_int32_1,0,quantity,int32,,1,-9999999,Checksum,0,,,,,,,,,,,,,
  BASE,,preferred_timestamp,PD16,preferred_timestamp_category_int8_str_int8_1,0,category<int8:str>,int8,"{0:'port_timestamp', 1:'driver_timestamp', 2:'internal_timestamp', 3:'time', -99:'empty'}",1,-99,Preferred Timestamp,0,,,,,,,,,Timestamp preferred as official record.,Reviewed-KS,,,
  BASE,,quality_flag,PD17,quality_flag_array_,0,array<>,,,,,,,,,,,,,,,,,,,
  BASE,,viz_timestamp,PD18,viz_timestamp_quantity_float64_seconds_since_1900_01_01,0,quantity,float64,,seconds since 1900-01-01,-9999999,"Timestamp, seconds since 1900-01-01",,FALSE,,,,,,,,,,,,
  BASE,,viz_product_type,PD19,viz_product_type_array_,0,array<>,,,,,,,,,,,,,,,,,,,
  BASE,,image_obj,PD20,image_obj_array_,0,array<>,,,,,Image object,0,,,,,,,,,,,,,
  
negative.code: BASE,,hc_data,PD1157,hc_data_array_,0,array<>,,,,,,0,,,,,,,,,,,,,
  BASE,,mpl_graph,PD24,mpl_graph_record_,0,record<>,,,,,,0,,,,,,,,,,,,,
  BASE,,dummy,PD25,dummy_quantity_int64_,0,quantity,int64,,,0,,0,,,,,,,,,,,,,
  BASE,,raw,PD26,raw_array_quantity_opaque_1,0,string,opaque,,1,,raw data,0,,,,,,,,,"Raw, unformatted data directly from instrument.",,,,
  BASE,,input_voltage,PD27,input_voltage_quantity_float64_volts,0,quantity,float64,,volts,-1,Input voltage,,,,,,,,,,,,,,
  BASE,PARAD,elapsed_time,PD28,elapsed_time_quantity_float64_s,0,quantity,float64,,s,-1,"Time since reset, seconds",,,,,,,,,,,,,,
  BASE,,pressure_temp,PD29,pressure_temp_quantity_float32_deg_C,0,quantity,float32,,deg_C,-9999,"Internal temperature at the pressure sensor, deg C",,,,,,,,,,"The temperature at the pressure sensor (inside the housing, but isolated from housing and the electronics.",,,,
  