states.Terrs = 0;
states.nerr_log = 0;
+ states.df = 0;
+ states.f1 = 0;
+ states.f2 = 0;
+ states.norm_rx_timing = 0;
+ states.ppm = 0;
+ states.prev_pkt = [];
+endfunction
+
+
+function states = fsk_horus_init_rtty_uw(states)
% Generate unque word that correlates against the ASCII "$$$$$" that
% delimits start and end of frame Note use of zeros in UW as "don't
% cares", we ignore RS232 start/stop bits. Not sure this is a good
states.uw = [mapped_db zeros(1,npad) mapped_db zeros(1,npad) mapped_db zeros(1,npad) mapped_db zeros(1,npad) mapped_db zeros(1,npad)];
states.uw_thresh = 5*7 - 4; % allow a few bit errors when looking for UW
+endfunction
- states.df = 0;
- states.f1 = 0;
- states.f2 = 0;
- states.norm_rx_timing = 0;
- states.ppm = 0;
- states.prev_pkt = [];
+
+
+function states = fsk_horus_init_binary_uw(states)
+ % Generate 16 bit "$$" unique word that is at the front of every horus binary
+ % packet
+
+ dollar_bits = [0 0 1 0 0 1 0 0];
+ mapped_db = 2*dollar_bits - 1;
+
+ states.uw = [mapped_db mapped_db];
+ states.uw_thresh = length(states.uw); % no bit errors when looking for UW
endfunction
% Extract as many ASCII packets as we can from a great big buffer of bits
-function extract_and_print_packets(states, rx_bits_log, rx_bits_sd_log)
+function extract_and_print_rtty_packets(states, rx_bits_log, rx_bits_sd_log)
% use UWs to delimit start and end of data packets
% simulation of tx and rx side, add noise, channel impairments ----------------------
function run_sim
- frames = 60;
- EbNodB = 8;
+ frames = 20;
+ EbNodB = 80;
timing_offset = 0.0; % see resample() for clock offset below
- test_frame_mode = 1;
+ test_frame_mode = 5;
fading = 0; % modulates tx power at 2Hz with 20dB fade depth,
% to simulate balloon rotating at end of mission
df = 0; % tx tone freq drift in Hz/s
more off
rand('state',1);
randn('state',1);
- states = fsk_horus_init(96000, 1200);
- states.f1_tx = 4000;
- states.f2_tx = 5200;
- states.verbose = 0x1 + 0x4;
+
+ % ----------------------------------------------------------------------
+
+ % sm2000 config ------------------------
+ %states = fsk_horus_init(96000, 1200);
+ %states.f1_tx = 4000;
+ %states.f2_tx = 5200;
+
+ if test_frame_mode == 4
+ % horus rtty config ---------------------
+ states = fsk_horus_init(8000, 100);
+ states.f1_tx = 1200;
+ states.f2_tx = 1600;
+ states.tx_bits_file = "horus_tx_bits_rtty.txt"; % Octave file of bits we FSK modulate
+ states = fsk_horus_init_rtty_uw(states);
+ end
+
+ if test_frame_mode == 5
+ % horus binary config ---------------------
+ states = fsk_horus_init(8000, 100);
+ states.f1_tx = 1200;
+ states.f2_tx = 1600;
+ states.tx_bits_file = "horus_tx_bits_binary.txt"; % Octave file of bits we FSK modulate
+ states = fsk_horus_init_binary_uw(states);
+ end
+
+ % ----------------------------------------------------------------------
+
+ states.verbose = 0x1;
N = states.N;
P = states.P;
Rs = states.Rs;
tx_bits(1:2:length(tx_bits)) = 1;
end
- if test_frame_mode == 4
+ if (test_frame_mode == 4) || (test_frame_mode == 5)
% load up a horus msg from disk and modulate that
- test_frame = load("horus_msg.txt");
+ test_frame = load(states.tx_bits_file);
ltf = length(test_frame);
ntest_frames = ceil((frames+1)*nsym/ltf);
tx_bits = [];
end
if test_frame_mode == 4
- extract_and_print_packets(states, rx_bits_log, rx_bits_sd_log)
+ extract_and_print_rtty_packets(states, rx_bits_log, rx_bits_sd_log)
+ end
+
+ if test_frame_mode == 5
+ printf("ltx_bits: %d lrx_bits_log: %d\n", length(tx_bits), length(rx_bits_log));
+ en = length(rx_bits_log);
+ uw_start = find_uw(states, 1, rx_bits_log)
+
+ % extract bytes and printf
+ pin = uw_start;
+ for i=1:45
+ rx_bytes(i) = rx_bits_log(pin:pin+7) * (2.^(7:-1:0))';
+ pin += 8;
+ printf("%d 0x%02x\n", i, rx_bytes(i));
+ end
+
+ f=fopen("horus_rx_bits_binary.txt","wt");
+ fwrite(f, rx_bytes, "uchar");
+ fclose(f);
end
figure(1);
% run test functions from here during development
if exist("fsk_horus_as_a_lib") == 0
- %run_sim;
- rx_bits = demod_file("horus.raw",4);
+ run_sim;
+ %rx_bits = demod_file("horus.raw",4);
%rx_bits = demod_file("~/Desktop/fsk_horus_10dB_1000ppm.wav",4);
%rx_bits = demod_file("~/Desktop/fsk_horus_6dB_0ppm.wav",4);
- % rx_bits = demod_file("test.raw",1,1);
+ %rx_bits = demod_file("test.raw",1,1);
%rx_bits = demod_file("/dev/ttyACM0",1);
%rx_bits = demod_file("fsk_horus_rx_1200_96k.raw",1);
%rx_bits = demod_file("mp.raw",4);
[ ] does it run fast enough on target?
[ ] test real time decode of both
- To test on a PC:
+ 1/ To test on a PC:
$ gcc horus_l2.c -o horus_l2 -Wall -DHORUS_L2_UNITTEST
$ ./horus_l2
payload data, at bit error rate (BER) of 0, 0.01, 0.05. It falls
over at a BER of 0.10 which is expected.
- To build with just the tx function, ie for linking with the payload
+ 2/ To build with just the tx function, ie for linking with the payload
firmware:
$ gcc horus_l2.c -c -Wall
By default the RX side is #ifdef-ed out, leaving the minimal amount
of code for tx.
+ 3/ Generate some tx_bits for testing with fsk_horus:
+
+ $ gcc horus_l2.c -o horus_l2 -Wall -DGEN_TX_BITS
+ $ ./horus_l2
+ $ more ../octave/horus_tx_bits_binary.txt
+
\*---------------------------------------------------------------------------*/
#include <assert.h>
horus_l2_encode_tx_packet() will need to store the tx packet
*/
-int horus_l2_get_num_tx_data_bytes(num_payload_data_bytes) {
+int horus_l2_get_num_tx_data_bytes(int num_payload_data_bytes) {
int num_payload_data_bits, num_golay_codewords;
int num_tx_data_bits, num_tx_data_bytes;
int main(void) {
int nbytes = 22;
- unsigned char input_payload[nbytes];
- int num_tx_data_bytes = horus_l2_get_num_tx_data_bytes(sizeof(input_payload));
unsigned char tx[num_tx_data_bytes];
+ unsigned char output_payload[nbytes];
int i;
for(i=0; i<nbytes; i++)
}
#endif
+
+#ifdef DEC_RX_BITS
+/* Decode a binary file rx_bytes, e.g. from fsk_horus.m */
+
+int main(void) {
+ int nbytes = 22;
+ unsigned char output_payload[nbytes];
+ int num_tx_data_bytes = horus_l2_get_num_tx_data_bytes(nbytes);
+ unsigned char rx[num_tx_data_bytes];
+ int i, ret;
+
+ FILE *f = fopen("../octave/horus_rx_bits_binary.txt","rb");
+ assert(f != NULL);
+ ret = fread(rx, sizeof(char), num_tx_data_bytes, f);
+ assert(ret == num_tx_data_bytes);
+ fclose(f);
+
+ golay23_init();
+ horus_l2_decode_rx_packet(output_payload, rx, nbytes);
+
+ fprintf(stderr, "\nOutput Payload:\n");
+ for(i=0; i<nbytes; i++)
+ fprintf(stderr, " %02d 0x%02x\n", i, output_payload[i]);
+
+ return 0;
+}
+#endif
+
/*---------------------------------------------------------------------------*\
GOLAY FUNCTIONS
projects / freetel-svn-tracking.git / commitdiff