Hyundai wheel speed counter is actually 4 bits spread over two signals

commaai · May 18, 2020 · 0610ed1 · 0610ed1
1 parent 0d581aa
commit 0610ed1
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Showing 2 changed files with 4 additions and 3 deletions.
diff --git a/board/safety/safety_hyundai.h b/board/safety/safety_hyundai.h
@@ -12,7 +12,7 @@ const CanMsg HYUNDAI_TX_MSGS[] = {{832, 0, 8}, {1265, 0, 4}, {1157, 0, 4}};
 AddrCheckStruct hyundai_rx_checks[] = {
   {.msg = {{608, 0, 8}}, .max_counter = 3U, .expected_timestep = 10000U},
   {.msg = {{897, 0, 8}}, .max_counter = 255U, .expected_timestep = 10000U},
-  {.msg = {{902, 0, 8}}, .max_counter = 3U,  .expected_timestep = 10000U},
+  {.msg = {{902, 0, 8}}, .max_counter = 15U,  .expected_timestep = 10000U},
   {.msg = {{916, 0, 8}}, .max_counter = 7U, .expected_timestep = 10000U},
   {.msg = {{1057, 0, 8}}, .max_counter = 15U, .expected_timestep = 20000U},
 };
@@ -27,7 +27,7 @@ static uint8_t hyundai_get_counter(CAN_FIFOMailBox_TypeDef *to_push) {
   } else if (addr == 897) {
     cnt = GET_BYTE(to_push, 5);
   } else if (addr == 902) {
-    cnt = (GET_BYTE(to_push, 1) >> 6) & 0x3;
+    cnt = ((GET_BYTE(to_push, 3) >> 6) << 2) | (GET_BYTE(to_push, 1) >> 6);
   } else if (addr == 916) {
     cnt = (GET_BYTE(to_push, 1) >> 5) & 0x7;
   } else if (addr == 1057) {

diff --git a/tests/safety/test_hyundai.py b/tests/safety/test_hyundai.py
@@ -53,7 +53,8 @@ def _brake_msg(self, brake):
   def _speed_msg(self, speed):
     # panda safety doesn't scale, so undo the scaling
     values = {"WHL_SPD_%s"%s: speed*0.03125 for s in ["FL", "FR", "RL", "RR"]}
-    values["WHL_SPD_AliveCounter_LSB"] = self.cnt_speed % 4
+    values["WHL_SPD_AliveCounter_LSB"] = (self.cnt_speed % 16) & 0x3
+    values["WHL_SPD_AliveCounter_MSB"] = (self.cnt_speed % 16) >> 2
     self.__class__.cnt_speed += 1
     return self.packer.make_can_msg_panda("WHL_SPD11", 0, values)