From fe738598dacd97149db738216fe4e574b8a926a7 Mon Sep 17 00:00:00 2001
From: Jerry Needell <jerryneedell@gmail.com>
Date: Fri, 20 Apr 2018 11:59:33 -0400
Subject: [PATCH]  modify tick.c to simplify - remove interupt disable from
 common_hal_pulseio_pulsein_resume

---
 ports/atmel-samd/common-hal/pulseio/PulseIn.c |  4 ----
 ports/atmel-samd/tick.c                       | 15 ++-------------
 2 files changed, 2 insertions(+), 17 deletions(-)

diff --git a/ports/atmel-samd/common-hal/pulseio/PulseIn.c b/ports/atmel-samd/common-hal/pulseio/PulseIn.c
index 0b551858c8..6e3aa3abb3 100644
--- a/ports/atmel-samd/common-hal/pulseio/PulseIn.c
+++ b/ports/atmel-samd/common-hal/pulseio/PulseIn.c
@@ -283,13 +283,9 @@ void common_hal_pulseio_pulsein_resume(pulseio_pulsein_obj_t* self,
     if (trigger_duration > 0) {
         gpio_set_pin_pull_mode(self->pin, GPIO_PULL_OFF);
         gpio_set_pin_direction(self->pin, GPIO_DIRECTION_OUT);
-        if(trigger_duration < 1000 ){  // only disable interrupts for < 1 ms
-            common_hal_mcu_disable_interrupts();
-        }
         gpio_set_pin_level(self->pin, !self->idle_state);
         common_hal_mcu_delay_us((uint32_t)trigger_duration);
         gpio_set_pin_level(self->pin, self->idle_state);
-        common_hal_mcu_enable_interrupts();
     }
 
     // Reconfigure the pin and make sure its set to detect the first edge.
diff --git a/ports/atmel-samd/tick.c b/ports/atmel-samd/tick.c
index 8a927785f4..72dddbe86f 100644
--- a/ports/atmel-samd/tick.c
+++ b/ports/atmel-samd/tick.c
@@ -60,26 +60,15 @@ void tick_delay(uint32_t us) {
     uint32_t ticks_per_us = common_hal_mcu_processor_get_frequency() / 1000 / 1000;
     uint32_t us_until_next_tick = SysTick->VAL / ticks_per_us;
     uint32_t start_tick;
-    while (us > 1000) {
-        // check if interrupts are disabled
-        if(__get_PRIMASK())
-           return; // if not just return
+    while (us > us_until_next_tick) {
         start_tick=SysTick->VAL;  // wait for SysTick->VAL to  RESET
         while (SysTick->VAL < start_tick) {}
         us -= us_until_next_tick;
         us_until_next_tick = 1000;
     }
-    if(us&&(us < us_until_next_tick)){
+    if(us){
         while (SysTick->VAL > ((us_until_next_tick - us) * ticks_per_us)) {}
     }
-    else {
-        start_tick=SysTick->VAL;  // wait for SysTick->VAL to  RESET
-        while (SysTick->VAL < start_tick) {}
-        us -= us_until_next_tick;
-        if(us){
-            while (SysTick->VAL > ((1000 - us) * ticks_per_us)) {}
-        }
-    }
 }
 
 // us counts down!