Store By Number - System Option

Utilities>System Options>System Wide>Purchase Orders 

Category-Configuration

Type- Must be Global 

If this is set to Yes, store codes designated as a letter, i.e., A, B, C, etc. will be converted to an ASCII numerical equivalent. 

This feature allows up to 254 store codes. 

If Store by Number is not used, the maximum number of store codes is 37 (blank, 0-9 and A-Z). 

A single character is simply an 8-bit range of memory. The same is true for a BYTE value, which allows values from 0. 255 (for practical purposes, we can only allow store numbers from 1.254).

This method allows many more store designations than a single character system.  Thus the numeric value for character "3" is in actuality ASCII value 51 (Store by Number stores are always presented with leading zeroes to make it easily distinguishable from store codes).

Once a store opts to use Store by Number, they should not attempt to revert. This feature was not designed to switch back and forth because there are many ASCII values that are "un-printable." If the Store by Number switch is selected, the next switch, Sequence Number by Store, is always disabled.