HP-71B: Newbie Question

[Dave Frederickson]

(06-17-2017 05:12 PM)smp Wrote:  So, since I already have a 4k RAM module and a 32K RAM module, and you say I can have up to 64K RAM, what would happen if I add a second 32K RAM module? Sure, while the first 32K RAM module is acting as indirect storage, that would be OK, but what if I attempt to claim the first 32K RAM module back into main memory? This is what's confusing me. Would I have to pull the 4K RAM module out?

I should have been clearer. What I meant is that you can install 64k modules in any available port. The 71 will reconfigure memory as you add and remove modules and it can address 512k of memory, so that means you could put 4-64k modules in the front port slots and a 128k module in the card reader port, for example.

You can leave the 4k module and install/remove the 32k module as desired. Just follow the rules for removing a memory module. That is, first convert the module to Independent RAM using the FREEPORT command, turn off the 71, then remove the module.

When the module is reinstalled it will have lost it's contents and will be configured as Main RAM.

Dave