Need help from someone that knows modern cash registers. I'm looking for an inexpensive modern cash register with tape printout, preferably with ink ribbon and a cash drawer. The kicker is the internal mechanism has to be entirely 12V. Most modern cash registers run on either 5V, 12V or 18V or a combination there of. I need one that is entirely 12V (ie. a single leg on the transformer to 12V) and can be easily converted to run on 12V battery for a farmers market. Can anyone help me with a brand and model number that would fit this bill?