diff --git a/ports/stm32/irq.c b/ports/stm32/irq.c
index 7298a4b504..0100899733 100644
--- a/ports/stm32/irq.c
+++ b/ports/stm32/irq.c
@@ -31,7 +31,7 @@
 /// \moduleref pyb
 
 #if IRQ_ENABLE_STATS
-uint32_t irq_stats[FPU_IRQn + 1] = {0};
+uint32_t irq_stats[IRQ_STATS_MAX] = {0};
 #endif
 
 /// \function wfi()
diff --git a/ports/stm32/irq.h b/ports/stm32/irq.h
index bfed17ecff..075791357c 100644
--- a/ports/stm32/irq.h
+++ b/ports/stm32/irq.h
@@ -39,7 +39,12 @@
 #define IRQ_ENABLE_STATS (0)
 
 #if IRQ_ENABLE_STATS
-extern uint32_t irq_stats[FPU_IRQn + 1];
+#if defined(STM32H7)
+#define IRQ_STATS_MAX   (256)
+#else
+#define IRQ_STATS_MAX   (128)
+#endif
+extern uint32_t irq_stats[IRQ_STATS_MAX];
 #define IRQ_ENTER(irq) ++irq_stats[irq]
 #define IRQ_EXIT(irq)
 #else