I will clean this mess but for now yay for the relative

src/data.cpp

@@ -0,0 +1,40 @@
+#include "data.h"
+#include <Arduino.h>
+#include <cstdint>
+#include <cstring>
+
+void SerializeDataPacket(DataPacket *p, uint8_t *buffer) {
+  size_t offset = 0;
+
+  memcpy(&p->StartMarker, buffer + offset, 1);
+  offset += 1;
+  Serial2.printf("\rStartMarker: 0x%02x\n", p->StartMarker);
+
+  memcpy(&p->speed, buffer + offset, speedLen);
+  offset += speedLen;
+  Serial2.printf("\rSpeed:       %s\n", p->speed);
+
+  memcpy(&p->gear, buffer + offset, gearLen);
+  offset += gearLen;
+  Serial2.printf("\rGear:        %s\n", p->gear);
+
+  memcpy(&p->rpm, buffer + offset, rpmLen);
+  offset += rpmLen;
+  Serial2.printf("\rRPM:         %s\n", p->rpm);
+
+  memcpy(&p->LapNumber, buffer + offset, lapNumberLen);
+  offset += lapNumberLen;
+  Serial2.printf("\rLapNumber:   %s\n", p->LapNumber);
+
+  memcpy(&p->currLapTime, buffer + offset, currLapTimeLen);
+  offset += currLapTimeLen;
+  Serial2.printf("\rcurrLapTime: %s\n", p->currLapTime);
+
+  memcpy(&p->lastLapTime, buffer + offset, lastLapTimeLen);
+  offset += lastLapTimeLen;
+  Serial2.printf("\rlastLapTime: %s\n", p->lastLapTime);
+
+  memcpy(&p->FuelEst, buffer + offset, FuelEstLen);
+  offset += FuelEstLen;
+  Serial2.printf("\rFuelEst:     %s\n", p->FuelEst);
+}