How the prototype looks like.
Five chips, xtal, Four resistors and decoupling cap in less than half square inch... Yes I do use magnifiers!! :-)
Preliminary info. (Please download the User's Guide from the link on the left for further details)
- 48K (12pages) Flash ROM distributed as follows:
4 pages (block 0) holding Advanced HEPAX emulation.
4 pages (block 1) to load primary user selected ROM images.
4 pages (block 2) to load secondary user selected ROM images.
Block 0 is always active providing HEPAX functionality.
Block 1 is active by default when the module is plugged. (uses ports 1 or 2)
Block 2 can be swaped with Block 1 by means of control word at address H'4100 (explained below)
Allowed pages for ROM blocks are #C to #F
Also both blocks can be disabled by means of such control word.
- 64K (16 pages) non volatile RAM.
4 blocks of 4 pages each, addressed to pages #8 to #B, can be used as HEPAX RAM or to hold ROM images the way Advanced HEPAX does.
Active RAM block is also selected by means of control word at H'4100. There always be an active RAM block.
- Control word usage:
HEXEDIT command allows direct access to any memory position.
Enter: 4100 at the [ADR: _ _ _ _ ] prompt.
You'll see [4100 100 _ _ _ ] (in binary: 01 0000 0000)
Meaning of control word's bits:
b9: 1=ROM block 2 enabled, 0=ROM block 2 disabled.
b8: 1=ROM block 1 enabled, 0=ROM block 1 disabled. (Set at plug-in)
b7-b2: Not used.
b1-b0: 00=RAM block 0 enabled, 01=RAM block 1 enabled, 10=RAM block 2 enabled, 11=... mmm, sure you can guess that one... :-)
Example 1: To enable ROM block 2 and select RAM block 3, write 203 into H'4100, then turn your HP-41 OFF and ON again.
Example 2: To Disable both ROM blocks and select RAM block 0, write 000 into H'4100, then turn your HP-41 OFF and ON again.
ROM block 1 has precedence over block 2. In case bits 9 & 8 were both set to 1 bit 9 will be erased leaving only ROM block 1 enabled.
Clearing bits 9 & 8 will disable both ROM block allowing the use of ports 3 and 4 to plug physical ROM modules in.
Changing the RAM block will be effective inmediately. To swap or disable ROM blocks power cycling the HP-41 is obviously needed.
It'll still take a few days to update this web page with fully detailed info, and include NoV-64 into the new Windows Configuration Utility, however any comments, questions and/or suggestions will be welcome.
NOTE on Clonix-D:
Though Clonix-D prototype is also finished, I'm aware that NoV-64 is more interesting for the community so I'll focus my effort during the next days to start the first production run.
To place an order for NoV-64 please use Pay-Pal account: email@example.com.
The Nov-64 is 175E, USB programmer adapter is 40E. Registered shipping and latest SW min-CD ROM are included.