diff --git a/src/fixkey-main.c b/src/fixkey-main.c
index 46e9817..3952340 100644
--- a/src/fixkey-main.c
+++ b/src/fixkey-main.c
@@ -30,7 +30,7 @@ static char *read_response(int serial_fd) {
     timer_start(3);
     while (true) {
         errno = 0;
-        uint8_t tmp[MAX_RESPONSE_LEN] = {0};
+        uint8_t tmp[RESPONSE_BUF_LEN] = {0};
         int bytes_read = read(serial_fd, tmp, RESPONSE_BUF_LEN);
         if (bytes_read < 0) {
             if (errno != EAGAIN || errno != EWOULDBLOCK) {