Creating a transmit raw functon that uses the msg fields directly.

Inc/tuk/can_wrapper/can_wrapper.h

@@ -83,4 +83,12 @@ CANWrapper_StatusTypeDef CANWrapper_Poll_Events();
  */
 CANWrapper_StatusTypeDef CANWrapper_Transmit(NodeID recipient, const CANMessage *msg);
 
+
+/**
+ * @brief               Sends a message over CAN with unusual values.
+ *
+ * @param recipient     ID of the intended recipient.
+ * @param msg           See CANMessage definition.
+ */
+CANWrapper_StatusTypeDef CANWrapper_Transmit_Raw(NodeID recipient, const CANMessage *msg);
 #endif /* CAN_WRAPPER_MODULE_INC_CAN_WRAPPER_H_ */

Src/can_wrapper/can_wrapper.c

@@ -180,6 +180,70 @@ CANWrapper_StatusTypeDef CANWrapper_Transmit(NodeID recipient, const CANMessage
 	return transmit_internal(recipient, msg, false);
 }
 
+
+
+CANWrapper_StatusTypeDef CANWrapper_Transmit_Raw(const CANMessage *msg)
+{
+	if (!s_init) return CAN_WRAPPER_NOT_INITIALISED;
+
+	if (HAL_CAN_GetState(s_init_struct.hcan) != HAL_CAN_STATE_READY &&
+			HAL_CAN_GetState(s_init_struct.hcan) != HAL_CAN_STATE_LISTENING)
+	{
+		return CAN_WRAPPER_TX_FAIL_BAD_CAN_STATE;
+	}
+
+	// Define the message header.
+	CAN_TxHeaderTypeDef tx_header = {0};
+	//use the message directly
+	tx_header.StdId = (msg->priority << 5 & PRIORITY_MASK)
+	                | (msg->sender         << 3 & SENDER_MASK)
+	                | (msg->recipient                      << 1 & RECIPIENT_MASK)
+	                | (msg->is_ack                              & ACK_MASK);
+
+	tx_header.IDE = CAN_ID_STD;   // We are using the standard identifier.
+	tx_header.RTR = CAN_RTR_DATA; // We are transmitting data.
+
+	tx_header.DLC = 1 + (msg->cmd).body_size; // Length = cmd ID + body.
+
+	// Wait to send CAN message.
+	uint16_t limiter = 0;
+	while (HAL_CAN_GetTxMailboxesFreeLevel(s_init_struct.hcan) == 0)
+	{
+		// return if mailboxes aren't being freed.
+		// for reasoning of the limit see:
+		// https://github.com/UMSATS/tsat-utilities-kit/issues/31#issuecomment-2287744661
+		if (limiter >= 4000) return CAN_WRAPPER_TX_MAILBOXES_FULL;
+		limiter++;
+	}
+
+	uint32_t tx_mailbox; // transmit mailbox.
+	HAL_StatusTypeDef status;
+	status = HAL_CAN_AddTxMessage(s_init_struct.hcan, &tx_header, (uint8_t*)&msg, &tx_mailbox);
+
+	if (status == HAL_OK && !msg->is_ack)
+	{
+		// Get timer variables.
+		uint32_t counter_value = __HAL_TIM_GET_COUNTER(s_init_struct.htim);
+		uint32_t rcr_value = s_init_struct.htim->Instance->RCR;
+
+		TxCacheItem tx_cache_item = {
+				.timestamp = {
+						.counter_value = counter_value,
+						.rcr_value = rcr_value
+				},
+				.msg = *msg;
+		};
+
+		// Copy over the message contents (command ID + body).
+		memcpy(&tx_cache_item.msg.cmd, &msg->cmd, CAN_MAX_BODY_SIZE+1);
+
+		TxCache_Push_Back(&s_tx_cache, &tx_cache_item);
+	}
+
+	return status;
+}
+
+
 static CANWrapper_StatusTypeDef transmit_internal(NodeID recipient, const CANMessage *msg, bool is_ack)
 {
 	if (!s_init) return CAN_WRAPPER_NOT_INITIALISED;
@@ -243,6 +307,8 @@ static CANWrapper_StatusTypeDef transmit_internal(NodeID recipient, const CANMes
 	return status;
 }
 
+
+
 // called by HAL when a new CAN message is received and pending.
 void HAL_CAN_RxFifo0MsgPendingCallback(CAN_HandleTypeDef *hcan)
 {