i'll got with this I guess

telemetry/data.go

@@ -1,8 +1,59 @@
 package telemetry
 
+import (
+	"bytes"
+	"encoding/binary"
+	"fmt"
+)
+
+type DataType uint8
+
+const (
+	DataTypeUINT8  DataType = 0
+	DataTypeINT8   DataType = 1
+	DataTypeUINT16 DataType = 2
+	DataTypeINT16  DataType = 3
+	DataTypeSTRING DataType = 4
+)
+
 type TelemetryField struct {
-	Parser func()
-	Value  any
+	Type  DataType
+	Value any
+}
+
+// Pack will pack this current TelemetryField into bytes to send over the wire
+// Format:
+// 0x00 - DataType
+// 0x01 - if its a (u)int8
+// or
+// 0x01 - if its a (u)int16 - first byte
+// 0x01 - if its a (u)int16 - second byte
+// or
+// 0x02 - str len max is 255 chars
+// [0x02] - str
+func (tf *TelemetryField) Pack() []byte {
+	buf := new(bytes.Buffer)
+
+	buf.WriteByte(uint8(tf.Type))
+
+	switch tf.Type {
+	case DataTypeINT8:
+		buf.WriteByte(uint8(tf.Value.(int8)))
+	case DataTypeUINT8:
+		buf.WriteByte(uint8(tf.Value.(uint8)))
+	case DataTypeINT16, DataTypeUINT16:
+		binary.Write(buf, binary.LittleEndian, tf.Value)
+	case DataTypeSTRING:
+		str := tf.Value.(string)
+		buf.WriteByte(uint8(len(str)))
+		buf.WriteString(str)
+	}
+
+	return buf.Bytes()
+}
+
+func (tf *TelemetryField) String() string {
+	return fmt.Sprintf("%v", tf.Value)
 }
 
 // NOTE: Replace values with a more appropriate custom field approach where

telemetry/data_test.go

@@ -0,0 +1,67 @@
+package telemetry
+
+import (
+	"bytes"
+	"math"
+	"testing"
+)
+
+func Test_TelemetryField(t *testing.T) {
+	type TFTest struct {
+		name   string
+		tf     TelemetryField
+		expect []byte
+	}
+
+	tests := []TFTest{
+		{
+			name: "test_max_uint8",
+			tf: TelemetryField{
+				Type:  DataTypeUINT8,
+				Value: uint8(math.MaxUint8),
+			},
+			expect: []byte{0x00, 0xFF},
+		},
+		{
+			name: "test_max_int8",
+			tf: TelemetryField{
+				Type:  DataTypeINT8,
+				Value: int8(math.MaxInt8),
+			},
+			expect: []byte{0x01, 0x7F},
+		},
+		{
+			name: "test_max_uint16",
+			tf: TelemetryField{
+				Type:  DataTypeUINT16,
+				Value: uint16(math.MaxUint16),
+			},
+			expect: []byte{0x02, 0xFF, 0xFF},
+		},
+		{
+			name: "test_max_int16",
+			tf: TelemetryField{
+				Type:  DataTypeINT16,
+				Value: int16(math.MaxInt16),
+			},
+			expect: []byte{0x03, 0xFF, 0x7F},
+		},
+		{
+			name: "test_string",
+			tf: TelemetryField{
+				Type:  DataTypeSTRING,
+				Value: "a cool string!",
+			},
+			expect: []byte{0x04, 0x0E, 0x61, 0x20, 0x63, 0x6F, 0x6F, 0x6C, 0x20, 0x73,
+				0x74, 0x72, 0x69, 0x6E, 0x67, 0x21},
+		},
+	}
+
+	for _, test := range tests {
+		result := test.tf.Pack()
+
+		if !bytes.Equal(result, test.expect) {
+			t.Errorf("\nTest: %s\nExpected: %v\nGot: %v\n", test.name, test.expect, result)
+		}
+	}
+}