diff --git a/bacnet-stack/src/bacapp.c b/bacnet-stack/src/bacapp.c
index 7ed8503d..260b1416 100644
--- a/bacnet-stack/src/bacapp.c
+++ b/bacnet-stack/src/bacapp.c
@@ -2089,10 +2089,32 @@ void testBACnetApplicationData(
         "Karg!", &value);
     ct_test(pTest, status == true);
     ct_test(pTest, testBACnetApplicationDataValue(&value));
+    /* test empty string */
+    status =
+        bacapp_parse_application_data(BACNET_APPLICATION_TAG_CHARACTER_STRING,
+        "", &value);
+    ct_test(pTest, status == true);
+    ct_test(pTest, testBACnetApplicationDataValue(&value));
 
     status =
         bacapp_parse_application_data(BACNET_APPLICATION_TAG_OCTET_STRING,
-        "Steve + Patricia", &value);
+        "1234567890ABCDEF", &value);
+    ct_test(pTest, status == true);
+    ct_test(pTest, testBACnetApplicationDataValue(&value));
+    status =
+        bacapp_parse_application_data(BACNET_APPLICATION_TAG_OCTET_STRING,
+        "12-34-56-78-90-AB-CD-EF", &value);
+    ct_test(pTest, status == true);
+    ct_test(pTest, testBACnetApplicationDataValue(&value));
+    status =
+        bacapp_parse_application_data(BACNET_APPLICATION_TAG_OCTET_STRING,
+        "12 34 56 78 90 AB CD EF", &value);
+    ct_test(pTest, status == true);
+    ct_test(pTest, testBACnetApplicationDataValue(&value));
+    /* test empty string */
+    status =
+        bacapp_parse_application_data(BACNET_APPLICATION_TAG_OCTET_STRING,
+        "", &value);
     ct_test(pTest, status == true);
     ct_test(pTest, testBACnetApplicationDataValue(&value));
 
diff --git a/bacnet-stack/src/bacstr.c b/bacnet-stack/src/bacstr.c
index a27176d3..d8ad3823 100644
--- a/bacnet-stack/src/bacstr.c
+++ b/bacnet-stack/src/bacstr.c
@@ -668,28 +668,34 @@ bool octetstring_init_ascii_hex(
 
     if (octet_string) {
         octet_string->length = 0;
-        while (ascii_hex[index] != 0) {
-            if (!isalnum(ascii_hex[index])) {
-                /* skip non-numeric or alpha */
-                index++;
-                continue;
+        if (ascii_hex[0] == 0) {
+            /* nothing to decode, so success! */
+            status = true;
+        } else {
+            while (ascii_hex[index] != 0) {
+                if (!isalnum(ascii_hex[index])) {
+                    /* skip non-numeric or alpha */
+                    index++;
+                    continue;
+                }
+                if (ascii_hex[index+1] == 0) {
+                    break;
+                }
+                hex_pair_string[0] = ascii_hex[index];
+                hex_pair_string[1] = ascii_hex[index+1];
+                value = (uint8_t)strtol(hex_pair_string, NULL, 16);
+                if (octet_string->length <= MAX_OCTET_STRING_BYTES) {
+                    octet_string->value[octet_string->length] = value;
+                    octet_string->length++;
+                        /* at least one pair was decoded */
+                    status = true;
+                } else {
+                    break;
+                    status = false;
+                }
+                /* set up for next pair */
+                index += 2;
             }
-            if (ascii_hex[index+1] == 0) {
-                break;
-            }
-            hex_pair_string[0] = ascii_hex[index];
-            hex_pair_string[1] = ascii_hex[index+1];
-            value = (uint8_t)strtol(hex_pair_string, NULL, 16);
-            if (octet_string->length <= MAX_OCTET_STRING_BYTES) {
-                octet_string->value[octet_string->length] = value;
-                octet_string->length++;
-                status = true;
-            } else {
-                break;
-                status = false;
-            }
-            /* set up for next pair */
-            index += 2;
         }
     }
 
diff --git a/bacnet-stack/src/ptransfer.c b/bacnet-stack/src/ptransfer.c
index 12e22d6f..23c05356 100644
--- a/bacnet-stack/src/ptransfer.c
+++ b/bacnet-stack/src/ptransfer.c
@@ -482,7 +482,7 @@ void test_Private_Transfer_Ack(
     BACNET_PRIVATE_TRANSFER_DATA test_data;
     uint8_t test_value[480] = { 0 };
     int private_data_len = 0;
-    char private_data_chunk[32] = { "I Love You, Patricia!" };
+    char private_data_chunk[33] = { "00112233445566778899AABBCCDDEEFF" };
     BACNET_APPLICATION_DATA_VALUE data_value;
     BACNET_APPLICATION_DATA_VALUE test_data_value;
     bool status = false;
@@ -535,7 +535,7 @@ void test_Private_Transfer_Error(
     BACNET_PRIVATE_TRANSFER_DATA test_data;
     uint8_t test_value[480] = { 0 };
     int private_data_len = 0;
-    char private_data_chunk[32] = { "I Love You, Patricia!" };
+    char private_data_chunk[33] = { "00112233445566778899AABBCCDDEEFF" };
     BACNET_APPLICATION_DATA_VALUE data_value;
     BACNET_APPLICATION_DATA_VALUE test_data_value;
     bool status = false;
@@ -584,7 +584,7 @@ void test_Private_Transfer_Request(
     uint8_t invoke_id = 128;
     uint8_t test_invoke_id = 0;
     int private_data_len = 0;
-    char private_data_chunk[32] = { "I Love You, Patricia!" };
+    char private_data_chunk[33] = { "00112233445566778899AABBCCDDEEFF" };
     BACNET_APPLICATION_DATA_VALUE data_value = {0};
     BACNET_APPLICATION_DATA_VALUE test_data_value = {0};
     BACNET_PRIVATE_TRANSFER_DATA private_data = {0};
@@ -638,7 +638,8 @@ void test_Unconfirmed_Private_Transfer_Request(
     private_data.vendorID = BACNET_VENDOR_ID;
     private_data.serviceNumber = 1;
 
-    status = bacapp_parse_application_data(BACNET_APPLICATION_TAG_OCTET_STRING,
+    status = bacapp_parse_application_data(
+        BACNET_APPLICATION_TAG_CHARACTER_STRING,
         &private_data_chunk[0], &data_value);
     ct_test(pTest, status == true);
     private_data_len =
diff --git a/bacnet-stack/test/bacapp.mak b/bacnet-stack/test/bacapp.mak
index f8d67f93..32211ad2 100644
--- a/bacnet-stack/test/bacapp.mak
+++ b/bacnet-stack/test/bacapp.mak
@@ -3,7 +3,8 @@ CC      = gcc
 
 SRC_DIR = ../src
 INCLUDES = -I../include -I.
-DEFINES = -DBIG_ENDIAN=0 -DTEST -DBACAPP_ALL -DTEST_BACNET_APPLICATION_DATA
+DEFINES = -DBIG_ENDIAN=0 -DTEST -DTEST_BACNET_APPLICATION_DATA
+DEFINES += -DBACAPP_ALL -DPRINT_ENABLED=1
 
 CFLAGS  = -Wall $(INCLUDES) $(DEFINES) -g
 
diff --git a/bacnet-stack/test/ptransfer.mak b/bacnet-stack/test/ptransfer.mak
index 2fb5fcd4..ac07e1db 100644
--- a/bacnet-stack/test/ptransfer.mak
+++ b/bacnet-stack/test/ptransfer.mak
@@ -2,7 +2,7 @@
 CC      = gcc
 SRC_DIR = ../src
 INCLUDES = -I../include -I.
-DEFINES = -DBIG_ENDIAN=0 -DTEST -DTEST_PRIVATE_TRANSFER
+DEFINES = -DBIG_ENDIAN=0 -PRINT_ENABLE=1 -DTEST -DTEST_PRIVATE_TRANSFER
 
 CFLAGS  = -Wall $(INCLUDES) $(DEFINES) -g
 
@@ -20,19 +20,19 @@ SRCS = $(SRC_DIR)/bacdcode.c \
 TARGET = ptransfer
 
 all: ${TARGET}
- 
+
 OBJS = ${SRCS:.c=.o}
 
 ${TARGET}: ${OBJS}
-	${CC} -o $@ ${OBJS} 
+	${CC} -o $@ ${OBJS}
 
 .c.o:
 	${CC} -c ${CFLAGS} $*.c -o $@
-	
+
 depend:
 	rm -f .depend
 	${CC} -MM ${CFLAGS} *.c >> .depend
-	
+
 clean:
 	rm -rf core ${TARGET} $(OBJS) *.bak *.1 *.ini