Add APDS9930

apds9930/apds9930.go

@@ -0,0 +1,231 @@
+package apds9930
+
+import (
+	"errors"
+
+	"tinygo.org/x/drivers"
+)
+
+var errInvalidParam = errors.New("apds9930: invalid param")
+
+type Dev struct {
+	bus    drivers.I2C
+	_txerr error
+	addr   uint16
+	buf    [3]byte
+}
+
+func New(bus drivers.I2C, addr uint8) Dev {
+	return Dev{bus: bus, addr: uint16(addr)}
+}
+
+// Status contains info on:
+//
+//	AVALID: Indicates that the ALS Ch0/Ch1 channels have completed an integration cycle.
+//	PSValid. Indicates that the PS has completed an integration cycle.
+//	AINTL ALS Interrupt. Indicates that the device is asserting an ALS interrupt
+//	PINT: Proximity Interrupt. Indicates that the device is asserting a proximity interrupt.
+//	PSAT: Proximity Saturation. Indicates that the proximity measurement is saturated
+type Status uint8
+
+func (s Status) ALSAvailable() bool         { return s&(1<<0) != 0 } // AVALID
+func (s Status) ProximityAvailable() bool   { return s&(1<<1) != 0 } // PVALID
+func (s Status) HasALSInterrupt() bool      { return s&(1<<4) != 0 } // AINT
+func (s Status) HasProxInterrupt() bool     { return s&(1<<5) != 0 } // PINT
+func (s Status) IsProximitySaturated() bool { return s&(1<<6) != 0 } // PSAT
+
+type Enable uint8
+
+const (
+	EnPower Enable = 1 << iota
+	EnALS
+	EnProx
+	EnWait
+	EnALSInt
+	EnProxInt
+	EnSleepAfterInt
+)
+
+// Luminic control gain.
+type ALSGain uint8
+
+const (
+	AGain1 ALSGain = iota
+	AGain8
+	AGain16
+	AGain120
+)
+
+type ProxGain uint8
+
+const (
+	PGain1 ProxGain = iota
+	PGain2
+	PGain4
+	PGain8
+)
+
+type Drive uint8
+
+const (
+	Drive100mA Drive = iota
+	Drive50mA
+	Drive25mA
+	Drive12_5mA
+)
+
+type Config struct {
+	ProxGain ProxGain
+	ALSGain  ALSGain
+	LEDDrive Drive
+}
+
+func (d *Dev) Init(cfg Config) error {
+	if cfg.LEDDrive > Drive100mA {
+		return errInvalidParam
+	}
+	d.txNew()
+	d.txWrite8(regENABLE, 0x00) // disable all features.
+	d.txWrite8(regATIME, 0xee)  // set default integration time.
+	d.txWrite8(regPPULSE, 0x04)
+	d.txWrite8(regWTIME, 0xee) // set default wait time.
+	d.txWrite8(regPTIME, 0xff) // set default pulse count.
+
+	var ctlval uint8 = 0b10 << 4 // Use Channel 1 diode.
+	ctlval |= uint8(cfg.LEDDrive&0b11) << 6
+	ctlval |= uint8(cfg.ProxGain&0b11) << 2
+	ctlval |= uint8(cfg.ALSGain & 0b11)
+	d.txWrite8(regCONTROL, ctlval)
+	return d.txErr()
+}
+
+func (d *Dev) Status() (Status, error) {
+	d.txNew()
+	v := d.txRead8(regSTATUS)
+	return Status(v), d.txErr()
+}
+
+// Enable sets the ENABLE register used primarily to
+// power the APDS-9930 device on/off, enable functions, and interrupts.
+// Arguments must be ORed, i.e: d.Enable(EnPower|EnProx); to enable proximity.
+func (d *Dev) Enable(en Enable) error {
+	en &= 0b01111111 // Seventh bit reserved.
+	d.txNew()
+	d.txWrite8(regENABLE, uint8(en))
+	return d.txErr()
+}
+
+func (d *Dev) enableLightSensor(withInterrupts bool) error {
+	return nil
+}
+
+func (d *Dev) setAmbientLightGain() {
+}
+
+func (d *Dev) EnableProximity() error {
+	return d.Enable(EnPower | EnALS | EnProx | EnWait)
+}
+
+func (d *Dev) proxIntLowThresh() (uint16, error) {
+	d.txNew()
+	return d.txRead16(regPILTL), d.txErr()
+}
+
+func (d *Dev) setProxIntLowThresh(loThresh uint16) error {
+	d.txNew()
+	d.txWrite16(regPILTL, loThresh)
+	return d.txErr()
+}
+
+func (d *Dev) proxIntHighThresh() (uint16, error) {
+	d.txNew()
+	val := d.txRead16(regPIHTL)
+	return val, d.txErr()
+}
+
+func (d *Dev) setProxIntHighThresh(hiThresh uint16) error {
+	d.txNew()
+	d.txWrite16(regPIHTL, hiThresh)
+	return d.txErr()
+}
+
+func (d *Dev) LEDDrive() (Drive, error) {
+	d.txNew()
+	val := (d.txRead8(regCONTROL) >> 6) & 0b11
+	return Drive(val), d.txErr()
+}
+
+// SetLEDDrive drive strength for proximity and ALS
+//
+//	Value    LED Current
+//	  3         100 mA
+//	  2         50 mA
+//	  1         25 mA
+//	  0         12.5 mA
+func (d *Dev) SetLEDDrive(drive Drive) error {
+	if drive > 3 {
+		return errInvalidParam
+	}
+	current, err := d.LEDDrive()
+	if err != nil {
+		return err
+	}
+	// Replace LED bits in Control register.
+	current &= 0b00111111
+	current |= drive << 6
+	d.txNew()
+	d.txWrite8(regCONTROL, uint8(current))
+	return d.txErr()
+}
+
+func (d *Dev) proxGain() (uint8, error) {
+	val := d.txRead8(regCONTROL)
+	return (val >> 2) & 0b11, d.txErr()
+}
+
+// ReadProximity returns a 10-bit value (0..1023), the higher the value the closer the object
+func (d *Dev) ReadProximity() uint16 {
+	d.txNew()
+	v := d.txRead16(regPDATAL)
+	if d.txErr() != nil {
+		return 0
+	}
+	return v
+}
+
+func (d *Dev) txRead16(addr uint8) uint16 {
+	if d.txErr() != nil {
+		return 0
+	}
+	d.buf[0] = addr | protoAutoInc
+	d._txerr = d.bus.Tx(d.addr, d.buf[:1], d.buf[1:3])
+	return uint16(d.buf[1]) | uint16(d.buf[2])<<8
+
+}
+
+func (d *Dev) txRead8(addr uint8) uint8 {
+	if d.txErr() != nil {
+		return 0
+	}
+	d.buf[0] = addr | protoAutoInc
+	d._txerr = d.bus.Tx(d.addr, d.buf[:1], d.buf[1:2])
+	return d.buf[1]
+}
+
+func (d *Dev) txWrite16(addr uint8, val uint16) {
+	d.txWrite8(addr, uint8(val))
+	d.txWrite8(addr+1, uint8(val>>8))
+}
+
+func (d *Dev) txWrite8(reg uint8, val uint8) {
+	if d.txErr() != nil {
+		return
+	}
+	d.buf[0] = reg | 0x80
+	d.buf[1] = val
+	d._txerr = d.bus.Tx(d.addr, d.buf[:2], nil)
+}
+
+func (d *Dev) txNew() { d._txerr = nil }
+
+func (d *Dev) txErr() error { return d._txerr }

apds9930/registers.go

@@ -0,0 +1,23 @@
+package apds9930
+
+const (
+	protoAutoInc = 0xA0
+)
+
+const (
+	regENABLE  = 0x00
+	regATIME   = 0x01
+	regPTIME   = 0x02
+	regWTIME   = 0x03
+	regPILTL   = 0x08
+	regPILTH   = 0x09
+	regPIHTL   = 0x0A
+	regPIHTH   = 0x0B
+	regCONFIG  = 0x0D
+	regPPULSE  = 0x0E
+	regCONTROL = 0x0F
+	regSTATUS  = 0x13
+	regPDATAL  = 0x18
+	regPDATAH  = 0x19
+	regPOFFSET = 0x1E
+)

examples/apds9930/proximity/proximity.go

@@ -0,0 +1,43 @@
+package main
+
+import (
+	"machine"
+	"time"
+
+	"tinygo.org/x/drivers/apds9930"
+)
+
+func main() {
+	// Sleep to catch any errors through the serial monitor.
+	time.Sleep(1000 * time.Millisecond)
+	bus := machine.I2C0
+	// use Nano 33 BLE Sense's internal I2C bus
+	err := bus.Configure(machine.I2CConfig{
+		SCL:       machine.GP1,
+		SDA:       machine.GP0,
+		Frequency: 100 * machine.KHz,
+	})
+	if err != nil {
+		panic(err.Error())
+	}
+	sensor := apds9930.New(bus, 0x39)
+
+	err = sensor.Init(apds9930.Config{})
+	if err != nil {
+		panic(err)
+	}
+	err = sensor.EnableProximity()
+	if err != nil {
+		panic(err)
+	}
+	println("proximity enabled!")
+	for {
+		stat, _ := sensor.Status()
+		if !stat.ProximityAvailable() {
+			time.Sleep(5 * time.Millisecond)
+			continue
+		}
+		prox := sensor.ReadProximity()
+		println("proximity:", prox)
+	}
+}