diff --git a/librfm69.c b/librfm69.c
index a030dac..36f81e3 100644
--- a/librfm69.c
+++ b/librfm69.c
@@ -238,14 +238,14 @@
 
 size_t rfmReadPayload(uint8_t *payload, size_t size) {
     size_t len = regRead(RFM_FIFO);
-    len = min(len, size);
+    size = min(len, size);
 
     // TODO assume and ignore address for now (already filtered anyway)
     regRead(RFM_FIFO);
 
     _rfmSel();
     _rfmTx(RFM_FIFO);
-    for (size_t i = 0; i < len; i++) {
+    for (size_t i = 0; i < size; i++) {
         payload[i] = _rfmTx(RFM_FIFO);
     }
     _rfmDes();