So, to recap, 1. We have a spreadsheet to create custom key maps for Tandy 200
2. Separately, we are trying to confirm in hardware that a single 27C64 rom can be substituted for M13, to implement the custom keymap. I would encourage the approach for dealing with different keyboards on other machines. Keep in mind.. if the actual characters themselves change, the modification is deeper. Such is the case for M10 for example. (Or just use the usa character set to make it easy). Thanks Steve