diff --git a/src/avr/gpio.c b/src/avr/gpio.c
index 9f947e7a..9919cdd1 100644
--- a/src/avr/gpio.c
+++ b/src/avr/gpio.c
@@ -143,7 +143,7 @@ gpio_out_setup(uint8_t pin, uint8_t val)
     if (! regs)
         goto fail;
     uint8_t bit = GPIO2BIT(pin);
-    uint8_t flag = irq_save();
+    irqstatus_t flag = irq_save();
     regs->out = val ? (regs->out | bit) : (regs->out & ~bit);
     regs->mode |= bit;
     irq_restore(flag);
@@ -160,7 +160,7 @@ void gpio_out_toggle(struct gpio_out g)
 void
 gpio_out_write(struct gpio_out g, uint8_t val)
 {
-    uint8_t flag = irq_save();
+    irqstatus_t flag = irq_save();
     g.regs->out = val ? (g.regs->out | g.bit) : (g.regs->out & ~g.bit);
     irq_restore(flag);
 }
@@ -174,7 +174,7 @@ gpio_in_setup(uint8_t pin, int8_t pull_up)
     if (! regs)
         goto fail;
     uint8_t bit = GPIO2BIT(pin);
-    uint8_t flag = irq_save();
+    irqstatus_t flag = irq_save();
     regs->out = pull_up > 0 ? (regs->out | bit) : (regs->out & ~bit);
     regs->mode &= ~bit;
     irq_restore(flag);
@@ -196,7 +196,7 @@ gpio_pwm_write(struct gpio_pwm g, uint8_t val)
     if (g.size8) {
         *(volatile uint8_t*)g.reg = val;
     } else {
-        uint8_t flag = irq_save();
+        irqstatus_t flag = irq_save();
         *(volatile uint16_t*)g.reg = val;
         irq_restore(flag);
     }
@@ -210,7 +210,7 @@ gpio_pwm_setup(uint8_t pin, uint32_t cycle_time, uint8_t val)
         if (READP(pwm_pins[chan]) != pin)
             continue;
         const struct gpio_pwm_info *p = &pwm_regs[chan];
-        uint8_t flags = READP(p->flags), cs;
+        irqstatus_t flags = READP(p->flags), cs;
         if (flags & GP_AFMT) {
             switch (cycle_time) {
             case 0        ...    8*510L - 1: cs = 1; break;
@@ -240,7 +240,7 @@ gpio_pwm_setup(uint8_t pin, uint32_t cycle_time, uint8_t val)
             shutdown("Can not user timer1 for PWM; timer1 is used for timers");
 
         // Setup PWM timer
-        uint8_t flag = irq_save();
+        irqstatus_t flag = irq_save();
         uint8_t old_cs = *regb & 0x07;
         if (old_cs && old_cs != cs)
             shutdown("PWM already programmed at different speed");
diff --git a/src/avr/irq.h b/src/avr/irq.h
index bfc6cb51..f586273a 100644
--- a/src/avr/irq.h
+++ b/src/avr/irq.h
@@ -15,13 +15,15 @@ static inline void irq_enable(void) {
     sei();
 }
 
-static inline uint8_t irq_save(void) {
+typedef uint8_t irqstatus_t;
+
+static inline irqstatus_t irq_save(void) {
     uint8_t flag = SREG;
     irq_disable();
     return flag;
 }
 
-static inline void irq_restore(uint8_t flag) {
+static inline void irq_restore(irqstatus_t flag) {
     barrier();
     SREG = flag;
 }
diff --git a/src/avr/serial.c b/src/avr/serial.c
index 33b42fc6..0a7a9508 100644
--- a/src/avr/serial.c
+++ b/src/avr/serial.c
@@ -89,7 +89,7 @@ console_pop_input(uint8_t len)
                     , needcopy - copied);
             copied = needcopy;
         }
-        uint8_t flag = irq_save();
+        irqstatus_t flag = irq_save();
         if (rpos != readb(&receive_pos)) {
             // Raced with irq handler - retry
             irq_restore(flag);
diff --git a/src/avr/timer.c b/src/avr/timer.c
index 442bff32..e4d7b942 100644
--- a/src/avr/timer.c
+++ b/src/avr/timer.c
@@ -52,7 +52,7 @@ timer_init(void)
 {
     if (CONFIG_AVR_CLKPR != -1 && (uint8_t)CONFIG_AVR_CLKPR != CLKPR) {
         // Program the clock prescaler
-        uint8_t flag = irq_save();
+        irqstatus_t flag = irq_save();
         CLKPR = 0x80;
         CLKPR = CONFIG_AVR_CLKPR;
         irq_restore(flag);
@@ -100,7 +100,7 @@ timer_periodic(void)
 uint32_t
 timer_read_time(void)
 {
-    uint8_t flag = irq_save();
+    irqstatus_t flag = irq_save();
     uint16_t cur = timer_get();
     uint32_t last = timer_last;
     irq_restore(flag);
diff --git a/src/basecmd.c b/src/basecmd.c
index 113cc30e..ab31efc2 100644
--- a/src/basecmd.c
+++ b/src/basecmd.c
@@ -30,7 +30,7 @@ move_free(struct move *m)
 struct move *
 move_alloc(void)
 {
-    uint8_t flag = irq_save();
+    irqstatus_t flag = irq_save();
     struct move *m = move_free_list;
     if (!m)
         shutdown("Move queue empty");
@@ -231,7 +231,7 @@ void
 command_debug_read16(uint32_t *args)
 {
     uint16_t *ptr = (void*)(size_t)args[0];
-    uint8_t flag = irq_save();
+    irqstatus_t flag = irq_save();
     uint16_t v = *ptr;
     irq_restore(flag);
     sendf("debug_result val=%hu", v);
@@ -251,7 +251,7 @@ void
 command_debug_write16(uint32_t *args)
 {
     uint16_t *ptr = (void*)(size_t)args[0];
-    uint8_t flag = irq_save();
+    irqstatus_t flag = irq_save();
     *ptr = args[1];
     irq_restore(flag);
 }
diff --git a/src/generic/irq.h b/src/generic/irq.h
index 597ff96d..0a56c657 100644
--- a/src/generic/irq.h
+++ b/src/generic/irq.h
@@ -3,9 +3,11 @@
 
 #include <stdint.h>
 
+typedef unsigned long irqstatus_t;
+
 void irq_disable(void);
 void irq_enable(void);
-uint8_t irq_save(void);
-void irq_restore(uint8_t flag);
+irqstatus_t irq_save(void);
+void irq_restore(irqstatus_t flag);
 
 #endif // irq.h
diff --git a/src/sched.c b/src/sched.c
index 539cb57b..99e37dd6 100644
--- a/src/sched.c
+++ b/src/sched.c
@@ -43,7 +43,7 @@ uint8_t
 sched_check_periodic(uint16_t time, uint16_t *pnext)
 {
     uint16_t next = *pnext, cur;
-    uint8_t flag = irq_save();
+    irqstatus_t flag = irq_save();
     cur = millis;
     irq_restore(flag);
     if ((int16_t)(cur - next) < 0)
@@ -82,7 +82,7 @@ void
 sched_timer(struct timer *add)
 {
     uint32_t waketime = add->waketime;
-    uint8_t flag = irq_save();
+    irqstatus_t flag = irq_save();
     if (sched_is_before(waketime, timer_list->waketime)) {
         // This timer is the next - insert at front of list and reschedule
         add->next = timer_list;
@@ -105,7 +105,7 @@ sched_timer(struct timer *add)
 void
 sched_del_timer(struct timer *del)
 {
-    uint8_t flag = irq_save();
+    irqstatus_t flag = irq_save();
     if (timer_list == del) {
         // Deleting the next active timer - delete and reschedule
         timer_list = del->next;
diff --git a/src/simulator/main.c b/src/simulator/main.c
index 419fa531..1bffc265 100644
--- a/src/simulator/main.c
+++ b/src/simulator/main.c
@@ -16,28 +16,32 @@
  * Interrupts
  ****************************************************************/
 
-uint8_t Interrupt_off;
+irqstatus_t Interrupt_off;
 
-void irq_disable(void)
+void
+irq_disable(void)
 {
     Interrupt_off = 1;
     barrier();
 }
 
-void irq_enable(void)
+void
+irq_enable(void)
 {
     barrier();
     Interrupt_off = 0;
 }
 
-uint8_t irq_save(void)
+irqstatus_t
+irq_save(void)
 {
-    uint8_t flag = Interrupt_off;
+    irqstatus_t flag = Interrupt_off;
     irq_disable();
     return flag;
 }
 
-void irq_restore(uint8_t flag)
+void
+irq_restore(irqstatus_t flag)
 {
     barrier();
     Interrupt_off = flag;