diff --git a/src/periph/fpga.cpp b/src/periph/fpga.cpp
index ca0a5beaa41c2fba05026d72a7538f6d5526c92c..937747a42aed4a0a1db9b0dd29fda1e61b8d6e0f 100644
--- a/src/periph/fpga.cpp
+++ b/src/periph/fpga.cpp
@@ -1115,7 +1115,7 @@ bool Periph_fpga::write_sst_offload_weighted_subbands(const char *data)
 {
     uint32_t _data[1];
     _data[0] = (uint32_t)data[0];
-    bool retval = Write("mm/0/REG_DP_SELECTOR/0/input_select", reg);
+    bool retval = Write("mm/0/REG_DP_SELECTOR/0/input_select", _data);
     return retval;
 }