diff --git a/src/dev/uart.c b/src/dev/uart.c
index 1cb356c..336bf9b 100644
--- a/src/dev/uart.c
+++ b/src/dev/uart.c
@@ -293,7 +293,7 @@ short uart_open(p_channel chan, const unsigned char * spec, short mode) {
         uart_setbps(cdev_to_uart(chan->dev), bps_code);
 
         // Get the next token
-        token = strtok_r(spec_copy, ",", &saveptr);
+        token = strtok_r(NULL, ",", &saveptr);
         if (token) {
             // Parse the data bit count
             i = atoi(token);
@@ -320,7 +320,7 @@ short uart_open(p_channel chan, const unsigned char * spec, short mode) {
             }
 
             // Get the next token
-            token = strtok_r(spec_copy, ",", &saveptr);
+            token = strtok_r(NULL, ",", &saveptr);
             if (token) {
                 // Parse the stop bit count (1 or 2)
                 i = atoi(token);
@@ -334,7 +334,7 @@ short uart_open(p_channel chan, const unsigned char * spec, short mode) {
                 }
 
                 // Get the next token
-                token = strtok_r(spec_copy, ",", &saveptr);
+                token = strtok_r(NULL, ",", &saveptr);
                 if (token) {
                     // NONE, ODD, EVEN, MARK, or SPACE
                     if (strcmp(token, "NONE") == 0) {