From bd5965957d6f91e7e20abf1412b7ace1f0cb3e43 Mon Sep 17 00:00:00 2001
From: "D.R.racer" <drracer@drracer.eu>
Date: Wed, 7 Sep 2022 15:13:38 +0200
Subject: [PATCH] Fix computation of CRC

came out of unit tests of read/write registers functionality.
---
 src/modules/protocol.h                        | 4 ++--
 tests/unit/application/test_application.cpp   | 2 +-
 tests/unit/modules/protocol/test_protocol.cpp | 5 +++--
 version.cmake                                 | 2 +-
 4 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/src/modules/protocol.h b/src/modules/protocol.h
index 434c5ad..bee500b 100644
--- a/src/modules/protocol.h
+++ b/src/modules/protocol.h
@@ -8,7 +8,7 @@ namespace modules {
 /// @brief The MMU communication protocol implementation and related stuff.
 ///
 /// See description of the new protocol in the MMU 2021 doc
-/// @@TODO possibly add some checksum to verify the correctness of messages
+
 namespace protocol {
 
 /// Definition of request message codes
@@ -58,7 +58,7 @@ struct RequestMsg {
         uint8_t crc = 0;
         crc = modules::crc::CRC8::CCITT_updateCX(0, (uint8_t)code);
         crc = modules::crc::CRC8::CCITT_updateCX(crc, value);
-        crc = modules::crc::CRC8::CCITT_updateCX(crc, value2);
+        crc = modules::crc::CRC8::CCITT_updateW(crc, value2);
         return crc;
     }
 
diff --git a/tests/unit/application/test_application.cpp b/tests/unit/application/test_application.cpp
index 17f5997..43cc5c1 100644
--- a/tests/unit/application/test_application.cpp
+++ b/tests/unit/application/test_application.cpp
@@ -9,5 +9,5 @@ TEST_CASE("application::ReportVersion", "[application]") {
 
     application.ReportReadRegister(mp::RequestMsg(mp::RequestMsgCodes::Version, 0));
 
-    REQUIRE(modules::serial::tx == "S0 A2*54\n");
+    REQUIRE(modules::serial::tx == "S0 A2*37\n");
 }
diff --git a/tests/unit/modules/protocol/test_protocol.cpp b/tests/unit/modules/protocol/test_protocol.cpp
index 130db60..4b4a086 100644
--- a/tests/unit/modules/protocol/test_protocol.cpp
+++ b/tests/unit/modules/protocol/test_protocol.cpp
@@ -65,8 +65,9 @@ std::string MakeCRC(const std::string_view src) {
     // code
     uint8_t crc = modules::crc::CRC8::CCITT_updateCX(0, src[0]);
     // scan hex value
-    uint16_t rqValue = std::stoul(src.data() + 1, nullptr, 16);
-    crc = modules::crc::CRC8::CCITT_updateW(crc, rqValue);
+    uint8_t rqValue = std::stoul(src.data() + 1, nullptr, 16);
+    crc = modules::crc::CRC8::CCITT_updateCX(crc, rqValue);
+    crc = modules::crc::CRC8::CCITT_updateW(crc, 0);
     if (!src[2])
         return MakeCRC(crc); // eof
     // [2] is a space
diff --git a/version.cmake b/version.cmake
index 1c718ed..2d8cbbf 100644
--- a/version.cmake
+++ b/version.cmake
@@ -10,6 +10,6 @@ set(PROJECT_VERSION_MINOR
     CACHE STRING "Project minor version" FORCE
     )
 set(PROJECT_VERSION_REV
-    2
+    3
     CACHE STRING "Project revision" FORCE
     )