From 71400d7128b59577729a20c4e998fe1d3f83d342 Mon Sep 17 00:00:00 2001
From: Giovanni Harting <539@idlegandalf.com>
Date: Tue, 12 Dec 2017 23:32:09 +0100
Subject: [PATCH] refined pulse handling

---
 main.go    |  4 ++--
 pca9685.go | 40 ++++++++++++++++++++--------------------
 2 files changed, 22 insertions(+), 22 deletions(-)

diff --git a/main.go b/main.go
index 0c0b5af..aae7acc 100644
--- a/main.go
+++ b/main.go
@@ -32,8 +32,8 @@ type config struct {
 	Pca9685 struct {
 		Device   string
 		Address  int
-		MinPulse int
-		MaxPulse int
+		MinPulse uint16
+		MaxPulse uint16
 	}
 }
 
diff --git a/pca9685.go b/pca9685.go
index fe7a6c2..c07b5af 100644
--- a/pca9685.go
+++ b/pca9685.go
@@ -23,15 +23,15 @@ const (
 	ALL_LED_OFF_H byte = 0xFD
 	OUTDRV        byte = 0x04
 	SLEEP         byte = 0x10
-	BYTE          byte = 0xFF
+	WORD          byte = 0xFF
 )
 
 type PCA9685 struct {
 	i2cBus    *i2c.Device
 	name      string
 	initiated bool
-	minPulse  int
-	maxPulse  int
+	minPulse  uint16
+	maxPulse  uint16
 	log       *logging.Logger
 	frequency float32
 }
@@ -42,7 +42,7 @@ type Pwm struct {
 	lastValue float32
 }
 
-func createPCA9685(i2cDevice *i2c.Device, name string, minPulse int, maxPulse int, log *logging.Logger) *PCA9685 {
+func createPCA9685(i2cDevice *i2c.Device, name string, minPulse uint16, maxPulse uint16, log *logging.Logger) *PCA9685 {
 	log.Info(fmt.Sprintf("Creating a new PCA9685 device. Alias: %v", name))
 
 	return &PCA9685{
@@ -89,7 +89,7 @@ func (p *PCA9685) Init() {
 			return
 		}
 
-		mode1 &= BYTE
+		mode1 &= WORD
 		mode1 = mode1 & ^SLEEP
 
 		p.i2cBus.WriteReg(MODE1, []byte{mode1 & 0xFF})
@@ -155,48 +155,48 @@ func (p *PCA9685) setPwmFreq(freqHz float32) {
 		p.log.Error("Can't read!")
 	}
 
-	oldMode &= BYTE
+	oldMode &= WORD
 
 	newMode := (oldMode & 0x7F) | 0x10
 
-	p.i2cBus.WriteReg(MODE1, []byte{newMode & BYTE})
-	p.i2cBus.WriteReg(PRESCALE, []byte{byte(prescale) & BYTE})
-	p.i2cBus.WriteReg(MODE1, []byte{oldMode & BYTE})
+	p.i2cBus.WriteReg(MODE1, []byte{newMode & WORD})
+	p.i2cBus.WriteReg(PRESCALE, []byte{byte(prescale) & WORD})
+	p.i2cBus.WriteReg(MODE1, []byte{oldMode & WORD})
 
 	time.Sleep(5 * time.Millisecond)
 
-	p.i2cBus.WriteReg(MODE1, []byte{oldMode&BYTE | 0x80})
+	p.i2cBus.WriteReg(MODE1, []byte{oldMode&WORD | 0x80})
 }
 
-func (p *PCA9685) setAllPwm(on int, off int) {
+func (p *PCA9685) setAllPwm(on uint16, off uint16) {
 	onB := byte(on)
 	offB := byte(off)
 
-	p.i2cBus.WriteReg(ALL_LED_ON_L, []byte{onB & BYTE})
-	p.i2cBus.WriteReg(ALL_LED_ON_H, []byte{onB & BYTE})
-	p.i2cBus.WriteReg(ALL_LED_OFF_L, []byte{offB & BYTE})
-	p.i2cBus.WriteReg(ALL_LED_OFF_H, []byte{offB & BYTE})
+	p.i2cBus.WriteReg(ALL_LED_ON_L, []byte{onB & WORD})
+	p.i2cBus.WriteReg(ALL_LED_ON_H, []byte{onB & WORD})
+	p.i2cBus.WriteReg(ALL_LED_OFF_L, []byte{offB & WORD})
+	p.i2cBus.WriteReg(ALL_LED_OFF_H, []byte{offB & WORD})
 }
 
-func (p *PCA9685) setPwm(pwm int, on int, off int) {
+func (p *PCA9685) setPwm(pwm int, on uint16, off uint16) {
 	onB := byte(on)
 	offB := byte(off)
 
-	p.i2cBus.WriteReg(LED0_ON_L+byte(4)*byte(pwm), []byte{onB & BYTE})
+	p.i2cBus.WriteReg(LED0_ON_L+byte(4)*byte(pwm), []byte{onB & WORD})
 	p.i2cBus.WriteReg(LED0_ON_H+byte(4)*byte(pwm), []byte{onB >> 8})
-	p.i2cBus.WriteReg(LED0_OFF_L+byte(4)*byte(pwm), []byte{offB & BYTE})
+	p.i2cBus.WriteReg(LED0_OFF_L+byte(4)*byte(pwm), []byte{offB & WORD})
 	p.i2cBus.WriteReg(LED0_OFF_H+byte(4)*byte(pwm), []byte{offB >> 8})
 }
 
 func (pwm *Pwm) setPercentage(percentage float32) error {
-	if percentage < 0.0 || percentage > 100.0 || pwm.pca.maxPulse > 4095 {
+	if percentage < 0.0 || percentage > 100.0 || pwm.pca.maxPulse > 65536 {
 
 		return errors.New(fmt.Sprintf("Percentage must be between 0.0 and 100.0. Got %v.", percentage))
 	}
 
 	pwm.pca.log.Info(fmt.Sprintf("Setting pwm #%v to %v%% at \"%v\" device.", pwm.pin, percentage, pwm.pca.name))
 
-	pwm.pca.setPwm(pwm.pin, 0, int(percentage*float32(pwm.pca.maxPulse)))
+	pwm.pca.setPwm(pwm.pin, 0, uint16(percentage*float32(pwm.pca.maxPulse)))
 
 	return nil
 }