I have a er-a320 sharp and when i turn it om it shows code E5-F0.27 hoe do i fix it

If the Sharp ER-A320 cash register has lost its settings after being unplugged and plugged back in, you may need to reprogram the register. Here are some steps you can follow: Consult the user manual: The user manual for the ER-A320 should have instructions for programming the register. If you don't have a physical copy of the manual, you can search for it online or contact Sharp customer support for assistance. Check the backup battery: The ER-A320 has a backup battery that helps to retain the programming in case of a power outage or unplugging. If the battery is dead or weak, it may have contributed to the loss of settings. You can check the battery and replace it if necessary. Reprogram the register: Using the manual or instructions provided by Sharp, you can reprogram the register with the necessary settings. This will likely involve resetting the register, entering your store information, setting up departments, programming PLUs, and setting up tax rates. Test the register: Once the programming is complete, you should test the register to make sure it is functioning properly. You can perform test transactions and ensure that the correct receipts are printed and that the totals are correct. If you are not comfortable reprogramming the register yourself, you can contact a Sharp authorized service center for assistance.

https://www.manualslib.com/manual/706368/Sharp-Er-A320.html?page=4#manual

This might help: https://www.manualslib.com/manual/158617/Sharp-Er-A410.html

See section on power-saving mode.

They are unmarked positions because they are special technician service modes. They are after the PGM position as you turn the key anti-clockwise. You need the SRV key to turn to those positions. Once you are in SRV position, use the programming manual to perform service programming. One of the users has it here:
https://the-checkout-tech.com/manuals/cashregisters/Sharp_ER-A320_programming_manual.html

Possibly clerk or cashier number?

Hi. It's an Epson type printer and the ink roller code number is IR91. You can still get them from many office supply companies, or on the net.

Receipt can be set to simple format or detailed format. All are depending on the setting by programming, like change job # 904, 905, 908, 909 ... some sale information may be omitted or added on.

ccd hand held

You have to activate gt sequence first

The letter H appears in the screen. The register will not respond. Any idea to what the Letter H means?