TI-66 double speed mod

[pauln]

(07-07-2022 10:23 PM)Didier Lachieze Wrote:  From: The "Personal Computer": A Fully Programmable Pocket Calculator

Thanks for the reference! At first glance, I'm not sure I completely understand but I will take a closer look.

Looking at the specs of the HP-65, it seems that one can go to a label but not to specific step (for the TI-59, you can go to either).

If this is true, then I can see that they implemented (in hardware) the program steps as a (circular) linked list instead of as an array.

Linked lists are notoriously fast for insertion/deletion. They are slow if one needs to access the nth element, but for the HP-65, one just needs a table that maps each of the (10?) labels to an address.

I wonder if the HP-65 has a way to go to step n (not necessarily at runtime) to inspect a particular step. For the TI-57, one can do that (not a runtime) with "GTO 2nd n".