I have a 7204 that every 10 seconds at the prompt the following appears and then a carrige return,
SD7204intr1#^@
SD7204intr1#^@
SD7204intr1#^@
SD7204intr1#^@
SD7204intr1#^@
SD7204intr1#^@
SD7204intr1#^@
If I do not complete my command in 10 seconds it will do a carrige return automatically.