fw: Tie together all parts for an end-to-end demo

7 files changed, 79 insertions, 21 deletions

diff --git a/controller/fw/src/crypto.c b/controller/fw/src/crypto.c
index db35745..f4f79a4 100644
--- a/controller/fw/src/crypto.c
+++ b/controller/fw/src/crypto.c
@@ -26,7 +26,7 @@ void debug_hexdump(const char *name, const uint8_t *buf, size_t len) {
     DEBUG_PRINTN("\n");
 }
 
-/* Returns 1 for correct trigger */
+/* Returns trigger sig height for correct trigger */
 int verify_trigger_dom(const uint8_t inkey[PRESIG_MSG_LEN],
         const char *domain_string, const uint8_t refkey[PRESIG_MSG_LEN]) {
     uint8_t key[crypto_auth_hmacsha512_KEYBYTES];
diff --git a/controller/fw/src/crypto.h b/controller/fw/src/crypto.h
index 05a3c0d..18a9816 100644
--- a/controller/fw/src/crypto.h
+++ b/controller/fw/src/crypto.h
@@ -3,7 +3,8 @@
 
 #include <stdint.h>
 
-#define PRESIG_MSG_LEN 16
+/* Presig message length: 15 byte = 120 bit ^= 20 * 6-bit symbols of 5-bit bipolar DSSS */
+#define PRESIG_MSG_LEN 15
 #define OOB_TRIGGER_LEN PRESIG_MSG_LEN
 
 enum trigger_domain {
diff --git a/controller/fw/src/main.c b/controller/fw/src/main.c
index 6547c38..e2f7353 100644
--- a/controller/fw/src/main.c
+++ b/controller/fw/src/main.c
@@ -15,6 +15,7 @@
 #include "dsss_demod.h"
 #include "con_usart.h"
 #include "mspdebug_wrapper.h"
+#include "crypto.h"
 
 static struct spi_flash_if spif;
 
@@ -28,6 +29,7 @@ unsigned int apb2_timer_speed = 0;
 struct leds leds;
 
 ssize_t jt_spi_flash_read_block(void *usr, int addr, size_t len, uint8_t *out);
+static void update_image_flash_counter(void);
 
 void __libc_init_array(void) { /* we don't need this. */ }
 void __assert_func (unused_a const char *file, unused_a int line, unused_a const char *function, unused_a const char *expr) {
@@ -208,7 +210,7 @@ ssize_t jt_spi_flash_read_block(void *usr, int addr, size_t len, uint8_t *out) {
     return len;
 }
 
-void update_image_flash_counter(void) {
+void update_image_flash_counter() {
     static int flash_counter = 0;
     flash_counter ++;
     fw_dump[row2_offx + 0] = flash_counter/10000 + '0';
@@ -222,6 +224,24 @@ void update_image_flash_counter(void) {
     fw_dump[row2_offx + 4] = flash_counter + '0';
 }
 
+/* Callback from crypto.c:oob_message_received */
+void oob_trigger_activated(enum trigger_domain domain, int serial) {
+    con_printf("oob_trigger_activated(%d, %d)\r\n", domain, serial);
+    con_printf("Attempting to flash meter...\r\n");
+    update_image_flash_counter();
+
+    int flash_tries = 0;
+    while (flash_tries++ < 25) {
+        mspd_jtag_init();
+        if (!mspd_jtag_flash_and_reset(jtag_img.devmem_img_start, jtag_img.img_len, jt_spi_flash_read_block, &jtag_img))
+            break;
+        for (int j=0; j<168*1000*5; j++)
+            asm volatile ("nop");
+    }
+    if (flash_tries == 25)
+        con_printf("Giving up.\r\n");
+}
+
 static unsigned int measurement_errors = 0;
 static struct dsss_demod_state demod_state;
 static uint32_t freq_sample_ts = 0;
@@ -264,17 +284,24 @@ int main(void)
     dsss_demod_init(&demod_state);
 
     con_printf("Booted.\r\n");
-    con_printf("Attempting to flash meter...\r\n");
-    int flash_tries = 0;
-    while (flash_tries++ < 25) {
-        mspd_jtag_init();
-        if (!mspd_jtag_flash_and_reset(jtag_img.devmem_img_start, jtag_img.img_len, jt_spi_flash_read_block, &jtag_img))
-            break;
-        for (int j=0; j<168*1000*5; j++)
-            asm volatile ("nop");
-    }
-    if (flash_tries == 25)
-        con_printf("Giving up.\r\n");
+
+
+    /* FIXME DEBUG */
+#if 0
+    uint8_t test_data[TRANSMISSION_SYMBOLS] = {
+        0
+    };
+    con_printf("Test 0\r\n");
+    handle_dsss_received(test_data);
+    
+    uint8_t test_data2[TRANSMISSION_SYMBOLS] = {
+        0x24, 0x0f, 0x3b, 0x10, 0x27, 0x0e, 0x22, 0x30, 0x01, 0x2c, 0x1c, 0x0b, 0x35, 0x0a, 0x12, 0x27, 0x11, 0x20,
+        0x0c, 0x10, 0xc0, 0x08, 0xa4, 0x72, 0xa9, 0x9b, 0x7b, 0x27, 0xee, 0xcd
+    };
+    con_printf("Test 1\r\n");
+    handle_dsss_received(test_data2);
+#endif
+    /* END DEBUG */
 
     while (23) {
         if (adc_fft_buf_ready_idx != -1) {
diff --git a/controller/fw/src/protocol.c b/controller/fw/src/protocol.c
index 4740917..6b7d8b7 100644
--- a/controller/fw/src/protocol.c
+++ b/controller/fw/src/protocol.c
@@ -1,9 +1,14 @@
 
+#include <assert.h>
+
 #include "sr_global.h"
 #include "dsss_demod.h"
 #include "con_usart.h"
+#include "rslib.h"
+#include "crypto.h"
 
 void handle_dsss_received(uint8_t data[static TRANSMISSION_SYMBOLS]) {
+    /* Console status output */
     con_printf("DSSS data received: ");
     for (int i=0; i<TRANSMISSION_SYMBOLS; i++) {
         int x = (data[i]>>1) * (data[i]&1 ? 1 : -1);
@@ -11,5 +16,29 @@ void handle_dsss_received(uint8_t data[static TRANSMISSION_SYMBOLS]) {
     }
     con_printf("\r\n");
 
-    update_image_flash_counter();
+    /* Run reed-solomon error correction */
+    const int sym_bits = DSSS_GOLD_CODE_NBITS + 1; /* +1 for amplitude sign bit */
+    /* TODO identify erasures in DSSS demod layer */
+    (void) rslib_decode(sym_bits, TRANSMISSION_SYMBOLS, (char *)data);
+    /* TODO error detection & handling */
+
+    /* Re-bit-pack data buffer to be bit-continuous:
+     *      [ . . a b  c d e f ] [ . . g h  i j k l ] [ . . m n  o p q r ] ...
+     *  ==> [ a b c d  e f g h ] [ i j k l  m n o p ] [ q r ...          ] ...
+     */
+    static_assert((TRANSMISSION_SYMBOLS - NPAR) * (DSSS_GOLD_CODE_NBITS + 1) == OOB_TRIGGER_LEN * 8);
+    for (uint8_t i=0, j=0; i < TRANSMISSION_SYMBOLS - NPAR; i++, j += sym_bits) {
+        uint32_t sym = data[i]; /* [ ... | . . X X  X X X X ] for 5-bit dsss */
+        data[i] = 0; /* clear for output */
+
+        sym <<= 8-sym_bits; /* left-align: [ ... | X X X X  X X . . ] */
+        sym <<= 8; /* shift to second byte: [ ... | X X X X  X X . . | . . . .  . . . . ]*/
+        sym >>= (j%8); /* shift to bit write offset: [ ... | . . . .  X X X X | X X . .  . . . . ] for offset 4 */
+        data[j/8] |= sym >> 8; /* write upper byte */
+        data[j/8 + 1] |= sym & 0xff; /* write lower byte */
+    }
+
+    /* hand off to crypto.c */ 
+    oob_message_received(data);
 }
+
diff --git a/controller/fw/src/rscode-config.h b/controller/fw/src/rscode-config.h
index 922aca9..ea5183b 100644
--- a/controller/fw/src/rscode-config.h
+++ b/controller/fw/src/rscode-config.h
@@ -3,7 +3,6 @@
 #ifndef __RSCODE_CONFIG_H__
 #define __RSCODE_CONFIG_H__
 
-#define NPAR 4
-#define NBITS 6
+#define NPAR 10
 
 #endif /* __RSCODE_CONFIG_H__ */
diff --git a/controller/fw/src/rslib.c b/controller/fw/src/rslib.c
index ce54a6f..aa0db2c 100644
--- a/controller/fw/src/rslib.c
+++ b/controller/fw/src/rslib.c
@@ -6,20 +6,19 @@
 
 #include "rslib.h"
 
+static struct rscode_driver driver;
+
 void rslib_encode(int nbits, size_t msglen, char msg[static msglen], char out[msglen + NPAR]) {
-    struct rscode_driver driver;
     rscode_init(&driver, nbits);
     rscode_encode(&driver, (unsigned char *)msg, msglen, (unsigned char *)out);
 }
 
 int rslib_decode(int nbits, size_t msglen, char msg_inout[static msglen]) {
-    struct rscode_driver driver;
     rscode_init(&driver, nbits);
     return rscode_decode(&driver, (unsigned char *)msg_inout, msglen);
 }
 
 int rslib_gexp(int z, int nbits) {
-    struct rscode_driver driver;
     rscode_init(&driver, nbits);
     return gexp(&driver, z);
 }
diff --git a/controller/fw/src/rslib.h b/controller/fw/src/rslib.h
index 3ef6d19..bba8bb0 100644
--- a/controller/fw/src/rslib.h
+++ b/controller/fw/src/rslib.h
@@ -1,9 +1,12 @@
 #ifndef __RSLIB_H__
 #define __RSLIB_H__
 
+/* parity length configuration */
+#include "rscode-config.h"
+
 void rslib_encode(int nbits, size_t msglen, char msg[static msglen], char out[msglen + NPAR]);
 int rslib_decode(int nbits, size_t msglen, char msg_inout[static msglen]);
 int rslib_gexp(int z, int nbits);
-size_t rslib_npar();
+size_t rslib_npar(void);
 
 #endif /* __RSLIB_H__ */