Casio Parts Cash Register PC Desktop "sharp stop beeping" Questions

...beeping noise and continues and doesnt stop until i unplug the machine or do a program reset. I have not tried oding a master reset and do not want to unless absolutly necesasry. Please help. Switch ...

...sharp cash register ER-A550S stop working my digital touch pad sharp cash register ER-A550S just not working at all All it shows is this sign -------- please help. when i push any key, does not type ...