From 4d88dfac9cd775738f9eb372cca0ce6dc8b470cf Mon Sep 17 00:00:00 2001
From: Terry Moore <tmm@mcci.com>
Date: Mon, 18 Mar 2019 23:30:50 -0400
Subject: [PATCH] Fix #267: compliance: count messages, don't use FcntDn

---
 src/lmic/lmic_compliance.c | 7 ++++++-
 src/lmic/lmic_compliance.h | 5 +++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/lmic/lmic_compliance.c b/src/lmic/lmic_compliance.c
index 222083f4..d46e1223 100644
--- a/src/lmic/lmic_compliance.c
+++ b/src/lmic/lmic_compliance.c
@@ -113,6 +113,9 @@ LMIC_complianceRxMessage(
 ) {
     lmic_compliance_state_t const complianceState = LMIC_Compliance.state;
 
+    // update the counter used by the status message.
+    ++LMIC_Compliance.downlinkCount;
+
     // filter normal messages.
     if (port != LORAWAN_PORT_COMPLIANCE) {
         return lmic_compliance_state_IsActive(complianceState)
@@ -202,6 +205,7 @@ Name:   evActivate()
 
 static void evActivate(void) {
     if (! lmic_compliance_state_IsActive(LMIC_Compliance.state)) {
+        LMIC_Compliance.downlinkCount = 0;
         LMIC_Compliance.eventflags |= LMIC_COMPLIANCE_EVENT_ACTIVATE;
         LMIC_Compliance.state = LMIC_COMPLIANCE_STATE_ACTIVATING;
 
@@ -665,7 +669,7 @@ static void acExitActiveMode(void) {
 
 static void acSendUplink(void) {
     uint8_t payload[2];
-    uint32_t const downlink = LMIC.seqnoDn;
+    uint32_t const downlink = LMIC_Compliance.downlinkCount;
 
     // build the uplink message
     payload[0] = (uint8_t) (downlink >> 8);
@@ -725,5 +729,6 @@ static void acDoJoin(void) {
     LMIC_Compliance.eventflags &= ~LMIC_COMPLIANCE_EVENT_JOINED;
 
     LMIC_unjoin();
+    LMIC_Compliance.downlinkCount = 0;
     LMIC_startJoining();
 }
diff --git a/src/lmic/lmic_compliance.h b/src/lmic/lmic_compliance.h
index ab326b3f..14853016 100644
--- a/src/lmic/lmic_compliance.h
+++ b/src/lmic/lmic_compliance.h
@@ -105,6 +105,11 @@ struct lmic_compliance_s {
         // uint32
         // uint16
 
+        // we are required to maintain a downlink count
+        // that is reset on join/test entry and incremented for
+        // each valid test message.
+        uint16_t                    downlinkCount;
+
         // uint8
 
         lmic_compliance_state_t         state;      // current state of compliance engine.