diff --git a/code/firmware/user/src/31fl3729.c b/code/firmware/user/src/31fl3729.c
index 01fe0ab..33f00cf 100644
--- a/code/firmware/user/src/31fl3729.c
+++ b/code/firmware/user/src/31fl3729.c
@@ -70,7 +70,7 @@ void is31fl3729_set_outputs(uint8_t i2c_addr, uint8_t sw, uint8_t *out, uint8_t
 
     // calculate start address
     sw--;
-    sw >>= 4;
+    sw <<= 4;
     sw++;
 
     i2c_write_addr1b(i2c_addr, sw, out, len);