public/antplusbridge
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

moved bluetooth function over to separate file

Browse Source
This commit is contained in:
Erik Brakkee 2026-05-26 17:31:07 +02:00
parent 10d8f6bb97
commit eb6fdd6b16
2 changed files with 83 additions and 74 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

82
cmd/bridge/bluetooth.go
View File

@ -1 +1,83 @@
package main
import (
"encoding/binary"
"fmt"
"math"
"time"
"tinygo.org/x/bluetooth"
)
var adapter = bluetooth.DefaultAdapter
func must(err error) {
if err != nil {
panic(err)
}
}
func ExposeBluetooth() {
must(adapter.Enable())
var powerChar bluetooth.Characteristic
must(adapter.AddService(&bluetooth.Service{
UUID: bluetooth.New16BitUUID(0x1818),
Characteristics: []bluetooth.CharacteristicConfig{
{
UUID: bluetooth.New16BitUUID(0x2A65), // Cycling Power Feature
Flags: bluetooth.CharacteristicReadPermission,
Value: []byte{0, 0, 0, 0},
},
{
UUID: bluetooth.New16BitUUID(0x2A63), // Cycling Power Measurement
Flags: bluetooth.CharacteristicNotifyPermission,
Handle: &powerChar,
},
},
}))
must(adapter.DefaultAdvertisement().Configure(bluetooth.AdvertisementOptions{
LocalName: "LinuxAntBtBridge",
ServiceUUIDs: []bluetooth.UUID{bluetooth.New16BitUUID(0x1818)},
}))
must(adapter.DefaultAdvertisement().Start())
fmt.Println("BLE advertising...")
var totalRevs float64
var lastCompletedRev float64 // time in 1/1024s of last completed revolution
lastUpdate := time.Now()
var elapsedTicks float64
for {
now := time.Now()
deltaT := now.Sub(lastUpdate).Seconds()
lastUpdate = now
sec := now.Second()
watts := uint16(100 + sec)
rpm := float64(50 + sec)
totalRevs += rpm / 60.0 * deltaT
elapsedTicks += deltaT * 1024.0
completedRevs := math.Floor(totalRevs)
// time at which the last completed revolution occurred
// = current time - fractional part of revolution * time per revolution
fracRev := totalRevs - completedRevs
timePerRev := 1024.0 * 60.0 / rpm
lastCompletedRev = elapsedTicks - fracRev*timePerRev
payload := make([]byte, 8)
binary.LittleEndian.PutUint16(payload[0:], 0x20)
binary.LittleEndian.PutUint16(payload[2:], watts)
binary.LittleEndian.PutUint16(payload[4:], uint16(completedRevs))
binary.LittleEndian.PutUint16(payload[6:], uint16(lastCompletedRev))
powerChar.Write(payload)
fmt.Printf("watts: %d rpm: %.0f completedRevs: %.0f lastRevTime: %.0f\n",
watts, rpm, completedRevs, lastCompletedRev)
time.Sleep(250 * time.Millisecond)
}
}

75
cmd/bridge/main.go
View File

@ -1,14 +1,10 @@
package main
import (
"encoding/binary"
"fmt"
"math"
"os/exec"
"time"
"github.com/google/gousb"
"tinygo.org/x/bluetooth"
)
func oldMain() {
@ -22,78 +18,9 @@ func oldMain() {
fmt.Println("channel closed")
}
var adapter = bluetooth.DefaultAdapter
func main() {
exec.Command("hciconfig", "hci0", "down").Run()
exec.Command("hciconfig", "hci0", "up").Run()
must(adapter.Enable())
var powerChar bluetooth.Characteristic
must(adapter.AddService(&bluetooth.Service{
UUID: bluetooth.New16BitUUID(0x1818),
Characteristics: []bluetooth.CharacteristicConfig{
{
UUID: bluetooth.New16BitUUID(0x2A65), // Cycling Power Feature
Flags: bluetooth.CharacteristicReadPermission,
Value: []byte{0, 0, 0, 0},
},
{
UUID: bluetooth.New16BitUUID(0x2A63), // Cycling Power Measurement
Flags: bluetooth.CharacteristicNotifyPermission,
Handle: &powerChar,
},
},
}))
must(adapter.DefaultAdvertisement().Configure(bluetooth.AdvertisementOptions{
LocalName: "LinuxAntBtBridge",
ServiceUUIDs: []bluetooth.UUID{bluetooth.New16BitUUID(0x1818)},
}))
must(adapter.DefaultAdvertisement().Start())
fmt.Println("BLE advertising...")
var totalRevs float64
var lastCompletedRev float64 // time in 1/1024s of last completed revolution
lastUpdate := time.Now()
var elapsedTicks float64
for {
now := time.Now()
deltaT := now.Sub(lastUpdate).Seconds()
lastUpdate = now
sec := now.Second()
watts := uint16(100 + sec)
rpm := float64(50 + sec)
totalRevs += rpm / 60.0 * deltaT
elapsedTicks += deltaT * 1024.0
completedRevs := math.Floor(totalRevs)
// time at which the last completed revolution occurred
// = current time - fractional part of revolution * time per revolution
fracRev := totalRevs - completedRevs
timePerRev := 1024.0 * 60.0 / rpm
lastCompletedRev = elapsedTicks - fracRev*timePerRev
payload := make([]byte, 8)
binary.LittleEndian.PutUint16(payload[0:], 0x20)
binary.LittleEndian.PutUint16(payload[2:], watts)
binary.LittleEndian.PutUint16(payload[4:], uint16(completedRevs))
binary.LittleEndian.PutUint16(payload[6:], uint16(lastCompletedRev))
powerChar.Write(payload)
fmt.Printf("watts: %d rpm: %.0f completedRevs: %.0f lastRevTime: %.0f\n",
watts, rpm, completedRevs, lastCompletedRev)
time.Sleep(250 * time.Millisecond)
}
}
func must(err error) {
if err != nil {
panic(err)
}
ExposeBluetooth()
}