diff --git a/ccsds_types.h b/ccsds_types.h
--- a/ccsds_types.h
+++ b/ccsds_types.h
@@ -687,21 +687,23 @@ typedef struct {
     unsigned char sy_lfr_s2_bp_p0;
     unsigned char sy_lfr_s2_bp_p1;
 
+    //************
+    // FBINS MASKS
     // mask F0
-    unsigned int sy_lfr_fbins_f0_word1;
-    unsigned int sy_lfr_fbins_f0_word2;
-    unsigned int sy_lfr_fbins_f0_word3;
-    unsigned int sy_lfr_fbins_f0_word4;
+    unsigned char sy_lfr_fbins_f0_word1[4];
+    unsigned char sy_lfr_fbins_f0_word2[4];
+    unsigned char sy_lfr_fbins_f0_word3[4];
+    unsigned char sy_lfr_fbins_f0_word4[4];
     // mask F1
-    unsigned int sy_lfr_fbins_f1_word1;
-    unsigned int sy_lfr_fbins_f1_word2;
-    unsigned int sy_lfr_fbins_f1_word3;
-    unsigned int sy_lfr_fbins_f1_word4;
+    unsigned char sy_lfr_fbins_f1_word1[4];
+    unsigned char sy_lfr_fbins_f1_word2[4];
+    unsigned char sy_lfr_fbins_f1_word3[4];
+    unsigned char sy_lfr_fbins_f1_word4[4];
     // mask F2
-    unsigned int sy_lfr_fbins_f2_word1;
-    unsigned int sy_lfr_fbins_f2_word2;
-    unsigned int sy_lfr_fbins_f2_word3;
-    unsigned int sy_lfr_fbins_f2_word4;
+    unsigned char sy_lfr_fbins_f2_word1[4];
+    unsigned char sy_lfr_fbins_f2_word2[4];
+    unsigned char sy_lfr_fbins_f2_word3[4];
+    unsigned char sy_lfr_fbins_f2_word4[4];
 
     // SPARE
     unsigned char source_data_spare;
diff --git a/fsw_params_nb_bytes.h b/fsw_params_nb_bytes.h
--- a/fsw_params_nb_bytes.h
+++ b/fsw_params_nb_bytes.h
@@ -34,6 +34,20 @@
 #define BYTE_POS_CP_MODE_LFR_SET            11
 #define BYTE_POS_CP_LFR_ENTER_MODE_TIME     12
 
+//TC_LFR_LOAD_FBINS_MASK
+#define DATAFIELD_POS_SY_LFR_FBINS_F0_WORD1 18   // 35 - 17
+#define DATAFIELD_POS_SY_LFR_FBINS_F0_WORD2 22
+#define DATAFIELD_POS_SY_LFR_FBINS_F0_WORD3 26
+#define DATAFIELD_POS_SY_LFR_FBINS_F0_WORD4 30
+#define DATAFIELD_POS_SY_LFR_FBINS_F1_WORD1 34
+#define DATAFIELD_POS_SY_LFR_FBINS_F1_WORD2 38
+#define DATAFIELD_POS_SY_LFR_FBINS_F1_WORD3 42
+#define DATAFIELD_POS_SY_LFR_FBINS_F1_WORD4 46
+#define DATAFIELD_POS_SY_LFR_FBINS_F2_WORD1 50
+#define DATAFIELD_POS_SY_LFR_FBINS_F2_WORD2 54
+#define DATAFIELD_POS_SY_LFR_FBINS_F2_WORD3 58
+#define DATAFIELD_POS_SY_LFR_FBINS_F2_WORD4 62 // 79 - 17
+
 // TC_LFR_LOAD_KCOEFFICIENTS
 #define NB_BYTES_PER_FLOAT 4
 #define DATAFIELD_POS_SY_LFR_KCOEFF_FREQUENCY 0 // 10 - 10