diff --git a/ws2812/ws2812_m4_64m.go b/ws2812/ws2812_m4_64m.go
index d5bef4d..b363a3a 100644
--- a/ws2812/ws2812_m4_64m.go
+++ b/ws2812/ws2812_m4_64m.go
@@ -1,4 +1,4 @@
-// +build nrf52
+// +build nrf52 nrf52840
 
 package ws2812