From 3bfba27dadbca545bf95bac75e7c806de3be54db Mon Sep 17 00:00:00 2001
From: DiscreteTom <discrete_tom@outlook.com>
Date: Sun, 24 Apr 2022 17:19:49 +0800
Subject: [PATCH] fix raspi PWMPin.SetDutyCycle (#800)

raspi: PWMPin.SetDutyCycle
   - value 0 is allowed in pi blaster
   - for pi-blaster, duty should not going below 2us, unless the duty is 0
---
 platforms/raspi/pwm_pin.go | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/platforms/raspi/pwm_pin.go b/platforms/raspi/pwm_pin.go
index 57f08073f..d5373496c 100644
--- a/platforms/raspi/pwm_pin.go
+++ b/platforms/raspi/pwm_pin.go
@@ -83,9 +83,10 @@ func (p *PWMPin) SetDutyCycle(duty uint32) (err error) {
 	p.dc = duty
 
 	val := gobot.FromScale(float64(p.dc), 0, float64(p.period))
-
+	
 	// never go below minimum allowed duty for pi blaster
-	if val < 0.05 {
+	// unless the duty equals to 0
+	if val < 0.05 && val != 0 {
 		val = 0.05
 	}
 	return p.piBlaster(fmt.Sprintf("%v=%v\n", p.pin, val))