Extending the precision of Woodstock or Saturn based calculators

[Alejandro Paz(Germany)]

And I'd really like a higher resolution 48 , not kidding. I have this nice 160x104 LCD sitting on my desk. Together with some 160x160, and that nice Sharp memory display at 400x240 (like what the DM42 has).

That is always the problem how to upgrade something without breaking everything that works.

On the speed:

I talk about the 1LF2 (HP-71):

One of the issues with the Saturn implementation is that with 4 bit memory width, you need as many cycles as nibbles to fetch the opcode. And then one extra cycle per calculated nibble.

With say 16 bit wide memory one could fetch many opcodes in one cycle, most in two. Extending the width of the internal alu to say 16 bits, that of course poses other "hurdles" on implementation but it is doable, one could execute word opcodes in 4 cycles, plus fetch.

A 64 bit parallel ALU could perform word opcodes in 1 cycle, needs 881 LUTs in a MachXO2, 4 A..D registers. Not bad.

There are a couple possibilities for incrementing the speed, rising the clock is one of them, but not the best without addressing memory bandwidth. The HP48 uses byte accesses, read-before-write for RAM. Lots of work, if one wants