From 4c854999bb66db369b279d576edad44936af6807 Mon Sep 17 00:00:00 2001
From: Christopher Young <cyoung@gmail.com>
Date: Wed, 24 May 2017 13:24:46 -0400
Subject: [PATCH 1/3] Reduce number of fan modes to 10 from 256. Add five
 second run-up at startup. #599, #595, #593.

---
 main/fancontrol.go | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/main/fancontrol.go b/main/fancontrol.go
index 58b552f2..8b210e4e 100644
--- a/main/fancontrol.go
+++ b/main/fancontrol.go
@@ -21,19 +21,16 @@ const (
 	defaultTempTarget = 50.
 	hysteresis        = float32(1.)
 
-	/* This puts our PWM frequency at 19.2 MHz / 128 =
-	/* 150kHz. Higher frequencies will reduce audible switching
-	/* noise but will be less efficient */
-	pwmClockDivisor = 128
+	pwmClockDivisor = 100
 
 	/* Minimum duty cycle is the point below which the fan does
 	/* not spin. This depends on both your fan and the switching
 	/* transistor used. */
-	defaultPwmDutyMin = 20
-	pwmDutyMax        = 256
+	defaultPwmDutyMin = 1
+	pwmDutyMax        = 10
 
 	// how often to update
-	delaySeconds = 2
+	delaySeconds = 30
 
 	// GPIO-1/BCM "18"/Pin 12 on a Raspberry PI 3
 	defaultPin = 1
@@ -50,7 +47,15 @@ var stdlog, errlog *log.Logger
 
 func fanControl(pwmDutyMin int, pin int, tempTarget float32) {
 	cPin := C.int(pin)
+
 	C.wiringPiSetup()
+
+	// Power on "test". Allows the user to verify that their fan is working.
+	C.pinMode(cPin, C.OUTPUT)
+	C.digitalWrite(cPin, C.HIGH)
+	time.Sleep(5 * time.Second)
+	C.digitalWrite(cPin, C.LOW)
+
 	C.pwmSetMode(C.PWM_MODE_BAL)
 	C.pinMode(cPin, C.PWM_OUTPUT)
 	C.pwmSetRange(pwmDutyMax)

From daee7316f5f9e8efa12e1b29b08172fadb58501c Mon Sep 17 00:00:00 2001
From: Christopher Young <cyoung@gmail.com>
Date: Wed, 24 May 2017 13:25:52 -0400
Subject: [PATCH 2/3] Switch from "BAL" mode to "MS" PWM modes. #599, #595,
 #593.

---
 main/fancontrol.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/main/fancontrol.go b/main/fancontrol.go
index 8b210e4e..4172e7b1 100644
--- a/main/fancontrol.go
+++ b/main/fancontrol.go
@@ -56,7 +56,7 @@ func fanControl(pwmDutyMin int, pin int, tempTarget float32) {
 	time.Sleep(5 * time.Second)
 	C.digitalWrite(cPin, C.LOW)
 
-	C.pwmSetMode(C.PWM_MODE_BAL)
+	C.pwmSetMode(C.PWM_MODE_MS)
 	C.pinMode(cPin, C.PWM_OUTPUT)
 	C.pwmSetRange(pwmDutyMax)
 	C.pwmSetClock(pwmClockDivisor)

From c3e4d613ca209f054e00ad4d43a7e7ca1e9c9e83 Mon Sep 17 00:00:00 2001
From: Christopher Young <cyoung@gmail.com>
Date: Wed, 24 May 2017 21:42:11 -0400
Subject: [PATCH 3/3] Remove full speed defaults.

#599, #595, #593.
---
 main/fancontrol.go | 12 ------------
 1 file changed, 12 deletions(-)

diff --git a/main/fancontrol.go b/main/fancontrol.go
index 4172e7b1..00c65ee0 100644
--- a/main/fancontrol.go
+++ b/main/fancontrol.go
@@ -69,21 +69,9 @@ func fanControl(pwmDutyMin int, pin int, tempTarget float32) {
 	})
 	pwmDuty := 0
 
-	tempWhenRampStarted := float32(0.)
 	for {
 		if temp > (tempTarget + hysteresis) {
-			if tempWhenRampStarted < 1. {
-				tempWhenRampStarted = temp
-			}
 			pwmDuty = iMax(iMin(pwmDutyMax, pwmDuty+1), pwmDutyMin)
-			if pwmDuty == pwmDutyMax {
-				// At the maximum duty cycle currently.
-				// Has the temperature increased "substantially" since the ramp-up started?
-				if temp > (tempWhenRampStarted + hysteresis) {
-					// Give up. The fan does not like the PWM control.
-					break
-				}
-			}
 		} else if temp < (tempTarget - hysteresis) {
 			pwmDuty = iMax(pwmDuty-1, 0)
 			if pwmDuty < pwmDutyMin {