diff --git a/cores/esp8266/core_esp8266_wiring_pwm.c b/cores/esp8266/core_esp8266_wiring_pwm.c
index a7647b348..9d16b62b7 100644
--- a/cores/esp8266/core_esp8266_wiring_pwm.c
+++ b/cores/esp8266/core_esp8266_wiring_pwm.c
@@ -94,18 +94,18 @@ void ICACHE_RAM_ATTR pwm_timer_isr(){
 	static uint16_t steps[17];
 	static uint32_t masks[17];
 	if(current_step < stepcount){
-    T1L = (pwm_steps[current_step+1] * pwm_multiplier);
-    TEIE |= TEIE1;
-    if(masks[current_step] & 0xFFFF) GPOC = masks[current_step] & 0xFFFF;
+		T1L = (pwm_steps[current_step+1] * pwm_multiplier);
+		TEIE |= TEIE1;
+		if(masks[current_step] & 0xFFFF) GPOC = masks[current_step] & 0xFFFF;
 		if(masks[current_step] & 0x10000) GP16O = 0;
 		current_step++;
 	} else {
 		current_step = 0;
 		stepcount = 0;
 		if(pwm_mask == 0) return;
-    T1L = (pwm_steps[current_step+1] * pwm_multiplier);
-    TEIE |= TEIE1;
-    if(pwm_mask & 0xFFFF) GPOS = pwm_mask & 0xFFFF;
+		T1L = (pwm_steps[current_step+1] * pwm_multiplier);
+		TEIE |= TEIE1;
+		if(pwm_mask & 0xFFFF) GPOS = pwm_mask & 0xFFFF;
 		if(pwm_mask & 0x10000) GP16O = 1;
 		stepcount = pwm_steps_len;
 		memcpy(steps, pwm_steps, (stepcount + 1) * 2);