diff --git a/bacnet-stack/mstp.c b/bacnet-stack/mstp.c
index 0e4a9e09..52016517 100644
--- a/bacnet-stack/mstp.c
+++ b/bacnet-stack/mstp.c
@@ -435,8 +435,7 @@ void MSTP_Receive_Frame_FSM(volatile struct mstp_port_struct_t *mstp_port)
                         of the data. */
                     /* Data */
                     if ((mstp_port->DataLength) &&
-                        (mstp_port->DataLength <= MAX_MPDU)) {
-                        /* FIXME: is limit InputBufferSize or MAX_MPDU? */
+                        (mstp_port->DataLength <= mstp_port->InputBufferSize)) {
                         /* Data - decode anyway to keep from false  */
                         mstp_port->Index = 0;
                         mstp_port->DataCRC = 0xFFFF;