HP-41 - Memory modules

[Sylvain Cote]

(04-10-2019 11:19 AM)albertofenini Wrote:  

(04-10-2019 05:11 AM)grsbanks Wrote:  Alberto, earlier you mentioned "Extended Memory" modules.

These have no influence on the number of registers available to store programs in or on the number of storage registers.

However, you then go on to mention the 82106A, which is a 64-Register add-on for "internal" memory and nothing to do with Extended Memory.

I'm confused now...

Sorry for the confusion, that shows how newbie I'm in this ...
I really meant the optional module 82016, and I have understood more with the previous replies
However, now I'm curious to know what the "extended memory" really is and what the difference is between the two
To me, and this is probably where the misunderstanding comes from, adding a module that raise the number of registers
(or programming steps) somehow extends the capabilities,
hence why I called this extended memory

FYI, This is the RAM memory map for the HP-41 related to the module and memory types

Code:

+-------------------------+-----------+------+--------------+--------------+
| Description             | Registers | Type | From Address |   To Address |
+-------------------------+-----+-----+------+--------------+--------------+
| 41C/CV/CX status registers    |  16 | main |    0 (0x000) |   15 (0x00F) |
+-------------------------------+-----+------+--------------+--------------+

Code:

+-------------------------------+-----+------+--------------+--------------+
| 41C  build-in memory          |  64 | main |  192 (0x0C0) |  255 (0x0FF) |
| 41C  +1 x 82106A memory       | 128 | main |  192 (0x0C0) |  319 (0x13F) |
| 41C  +2 x 82106A memory       | 192 | main |  192 (0x0C0) |  383 (0x17F) |
| 41C  +3 x 82106A memory       | 256 | main |  192 (0x0C0) |  447 (0x1BF) |
| 41C  +4 x 82106A memory       | 320 | main |  192 (0x0C0) |  511 (0x1FF) |
+-------------------------------+-----+------+--------------+--------------+
| 41C  +1 x 82170A quad memory  | 320 | main |  192 (0x0C0) |  511 (0x1FF) | replace 4x 82106A memory module, hence the name quad
+-------------------------------+-----+------+--------------+--------------+

Code:

+-------------------------------+-----+------+--------------+--------------+
| 41CV build-in memory          | 320 | main |  192 (0x0C0) |  511 (0x1FF) |
+-------------------------------+-----+------+--------------+--------------+
| 41CX build-in memory          | 320 | main |  192 (0x0C0) |  511 (0x1FF) |
| 41CX build-in extended-memory | 128 | ext. |   64 (0x040) |  191 (0x0BF) |
+-------------------------------+-----+------+--------------+--------------+

Code:

+-------------------------------+-----+------+--------------+--------------+
| 82180A x-fncs/memory module   | 128 | ext. |   64 (0x040) |  191 (0x0BF) | for the HP-41C/CV only, built-in in the CX
| 82181A x-memory first module  | 239 | ext. |  513 (0x201) |  751 (0x2EF) |
| 82181A x-memory second module | 239 | ext. |  769 (0x301) | 1007 (0x3EF) |
+-------------------------------+-----+------+--------------+--------------+

Code:

+-------------------------------+-----+------+--------------+--------------+
| Empty Space                   |  48 | none |   16 (0x010) |   63 (0x03F) |
| Empty Space                   |   1 | none |  512 (0x200) |  512 (0x200) |
| Empty Space                   |  17 | none |  752 (0x2F0) |  768 (0x300) |
| Empty Space                   |  16 | none | 1008 (0x3F0) | 1023 (0x3FF) |
+-------------------------------+-----+------+--------------+--------------+

edit: typo