Thank you for the explanations - it is somewhat clearer now, although WOW those Warp9 boards are costly ! ! ! I spent a few hours yesterday rebuilding an old parallel ported PC running Win7 - its so cute and slow compared to current Win10
But to think up until two years ago Win7 was my daily driver OS! So, as I have a licenced version of Mach3, I'll continue with that, as I don't currently do enough work to warrant the expenditure for an ESS and Mach4. Thanks again.