From af05b21daec5f45f6688cf0a7c095e48737f27b7 Mon Sep 17 00:00:00 2001
From: drowe67 <drowe67@01035d8c-6547-0410-b346-abe4f91aad63>
Date: Mon, 9 Apr 2018 02:50:03 +0000
Subject: [PATCH] exposed CRC function so horus_api can use it

git-svn-id: https://svn.code.sf.net/p/freetel/code@3456 01035d8c-6547-0410-b346-abe4f91aad63
---
 codec2-dev/src/horus_l2.c | 7 +++----
 codec2-dev/src/horus_l2.h | 3 +++
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/codec2-dev/src/horus_l2.c b/codec2-dev/src/horus_l2.c
index f3cdc73e..55fdc63a 100644
--- a/codec2-dev/src/horus_l2.c
+++ b/codec2-dev/src/horus_l2.c
@@ -70,7 +70,6 @@ static char uw[] = {'$','$'};
 int32_t get_syndrome(int32_t pattern);
 void golay23_init(void);
 int golay23_decode(int received_codeword);
-unsigned short gen_crc16(unsigned char* data_p, unsigned char length);
 void interleave(unsigned char *inout, int nbytes, int dir);
 void scramble(unsigned char *inout, int nbytes);
 
@@ -785,7 +784,7 @@ int main(void) {
     /* all zeros is nastiest sequence for demod before scrambling */
 
     memset(&input_payload, 0, nbytes);
-    input_payload.Checksum = gen_crc16((unsigned char*)&input_payload, nbytes-2);
+    input_payload.Checksum = horus_l2_gen_crc16((unsigned char*)&input_payload, nbytes-2);
 
     horus_l2_encode_tx_packet(tx, (unsigned char*)&input_payload, nbytes);
     
@@ -846,7 +845,7 @@ int main(void) {
     assert(sizeof(h) == nbytes);
     memcpy(&h, output_payload, nbytes);
 
-    uint16_t crc_rx = gen_crc16(output_payload, nbytes-2);
+    uint16_t crc_rx = horus_l2_gen_crc16(output_payload, nbytes-2);
     char crc_str[80];
     
     if (crc_rx == h.Checksum) {
@@ -1163,7 +1162,7 @@ int golay23_count_errors(int recd_codeword, int corrected_codeword)
 
 // from http://stackoverflow.com/questions/10564491/function-to-calculate-a-crc16-checksum
 
-unsigned short gen_crc16(unsigned char* data_p, unsigned char length){
+unsigned short horus_l2_gen_crc16(unsigned char* data_p, unsigned char length) {
     unsigned char x;
     unsigned short crc = 0xFFFF;
 
diff --git a/codec2-dev/src/horus_l2.h b/codec2-dev/src/horus_l2.h
index 7ded29ac..86a9d76e 100644
--- a/codec2-dev/src/horus_l2.h
+++ b/codec2-dev/src/horus_l2.h
@@ -12,6 +12,7 @@
 int horus_l2_get_num_tx_data_bytes(int num_payload_data_bytes);
 
 /* returns number of output bytes in output_tx_data */
+
 int horus_l2_encode_tx_packet(unsigned char *output_tx_data,
                               unsigned char *input_payload_data,
                               int            num_payload_data_bytes);
@@ -20,4 +21,6 @@ void horus_l2_decode_rx_packet(unsigned char *output_payload_data,
                                unsigned char *input_rx_data,
                                int            num_payload_data_bytes);
 
+unsigned short horus_l2_gen_crc16(unsigned char* data_p, unsigned char length);
+
 #endif
-- 
2.25.1