PX41CX

[agarza]

So, I really wanted the full functionality of the HP41CX for the PX DIY calculators.
But the ATMEGA328 has very limited memory (both flash and ram). Fortunately, there is a relatively new microcontroller from Microchip. Same physical size and thru hole (28 pins) but with lots of ram and flash.

So, here’s where I’m at:
- Clock/Timer with a resolution of 250ms (instead of the original 100ms)
- Full RAM (319 Registers)
- Full Extended Memory (600 Registers)
- Enough flash to store several modules. (Currently only tested with advantage module and Games module at once.)
- Consumes about 7µA in sleep mode. (The CR2032 coin battery should last more than 2 years)
- Same 192x64 LCD
- Same keypad
- Same landscape form as other PX calculators.

The idea is to make it in portrait form, like the original HP14C.

If anyone is interested in testing, please PM me.

[Massimo Gnerucci]

(10-29-2022 07:58 PM)agarza Wrote:  The idea is to make it in portrait form, like the original HP14C.

Ok, now you've got my attention

:)

[Liam Hays]

That would be awesome. What's the new chip you're looking at? The only -328-similar ones I know of are the ATmega3208/4809 series. Also, would it have USB to upload modules with, like a SwissMicros?

[SammysHP]

Hmm… maybe AVR32DD28?

[johnb]

(10-29-2022 07:58 PM)agarza Wrote:  So, I really wanted the full functionality of the HP41CX for the PX DIY calculators.

I'm intrigued, but all my DuckDuckGo searches (PX calculator, PX DIY calculator, PX DIY, etc) are showing clothing, PC calculators for pixel work, and other non-relateds. I can't find the project anywhere on line.

Please post a URL!

[Massimo Gnerucci]

Just search for PX41C, first link shown.

[agarza]

(10-31-2022 07:05 PM)johnb Wrote:  

(10-29-2022 07:58 PM)agarza Wrote:  So, I really wanted the full functionality of the HP41CX for the PX DIY calculators.

I'm intrigued, but all my DuckDuckGo searches (PX calculator, PX DIY calculator, PX DIY, etc) are showing clothing, PC calculators for pixel work, and other non-relateds. I can't find the project anywhere on line.

Please post a URL!

This is the project's page:
https://paxer.net/voyager/

[agarza]

(10-31-2022 03:53 PM)SammysHP Wrote:  Hmm… maybe AVR32DD28?

Getting warm...

I'm using the AVR128DA28

• running at up to 24 MHz
• with 128 KB of Flash
• 16 KB of SRAM
• and 512B of EEPROM
  

[Jlouis]

Very interesting, I read the site but I'm still in doubt, is there a way to install modules? Or it is already there?
Thanks for any enlightenment!

Cheers

[agarza]

(11-02-2022 01:19 AM)Jlouis Wrote:  Very interesting, I read the site but I'm still in doubt, is there a way to install modules? Or it is already there?
Thanks for any enlightenment!

Cheers

Currently, the only way to add modules to the PX41CX is to flash them along with the firmware.

Note that on the PX41C, there is no space left for modules.

[Jlouis]

(11-02-2022 02:43 AM)agarza Wrote:  

(11-02-2022 01:19 AM)Jlouis Wrote:  Very interesting, I read the site but I'm still in doubt, is there a way to install modules? Or it is already there?
Thanks for any enlightenment!

Cheers

Currently, the only way to add modules to the PX41CX is to flash them along with the firmware.

Note that on the PX41C, there is no space left for modules.

Really thanks for the prompt reply.

So, I'm only interested in PX41CX.

I really don't thing anyone here would be interested in a bare bone 41c clone.

If flash the firmware with most of the interesting modules is a possible and feasible way (at least for me) then I'm interested.

I will follow this thread with interest.

Cheers

JL

[Sylvain Cote]

(11-02-2022 02:43 AM)agarza Wrote:  Currently, the only way to add modules to the PX41CX is to flash them along with the firmware.

Are you sure ?

From what I am reading ...
1) the maximum directly Flash addressing space is 16 bits or 64 KB
2) the first 32KB is reserved for code, divided between boot code and app code while the second 32KB is reserved for data
3) of the 128KB Flash
3a) the first 32KB is reserved for code (mapped into the direct addressing space)
3b) and the last 96KB can be divided into three 32KB data blocks of which one can be mapped into the direct addressing space.
4) you also have three USART that can be used for RS232 transmission

So with code, you could come with a scheme that allows data transfer (ROM images) transfer over the serial interface and store the data into one of the three 32KB data pages.
You could then map a data page containing the ROMs into the address space. For sure it will be a little more complicated than that, but it seems doable.

[J-F Garnier]

(10-31-2022 01:50 PM)Liam Hays Wrote:  Also, would it have USB to upload modules with, like a SwissMicros?

(11-02-2022 05:18 AM)Sylvain Cote Wrote:  So with code, you could come with a scheme that allows data transfer (ROM images) transfer over the serial interface and store the data into one of the three 32KB data pages.
You could then map a data page containing the ROMs into the address space. For sure it will be a little more complicated than that, but it seems doable.

What I appreciate in agarza's designs is the simplicity and optimal use of the resources (I don't have a PX41C but the PX15).
So I would not ask for an equivalent of the DM41X or worst the 41CL.

Regarding modules, the question was already asked here and the Advantage surely is the obvious choice.
Which other built-in modules would we really need?

J-F

[Sylvain Cote]

(11-02-2022 08:29 AM)J-F Garnier Wrote:  What I appreciate in agarza's designs is the simplicity and optimal use of the resources (I don't have a PX41C but the PX15).

I can understand that.

(11-02-2022 08:29 AM)J-F Garnier Wrote:  So I would not ask for an equivalent of the DM41X or worst the 41CL.

Well, we are on the opposite side on this one.
For me, the 41CL is by far the best 41 there is.
I get a fast CPU, all the modules ROM images while still being able to use all the physical peripherals.

(11-02-2022 08:29 AM)J-F Garnier Wrote:  Regarding modules, the question was already asked here and the Advantage surely is the obvious choice.
Which other built-in modules would we really need?

Euh ... new modules from Ángel/others, CCD, ZenROM, modules that use QROM like HePaX/RAMBox/others, etc.

Anyway, even thought I am not the targeted audience here, I will probably buy one just to play with it, but that will be all.

Sylvain

[J-F Garnier]

(11-02-2022 02:49 PM)Sylvain Cote Wrote:  

(11-02-2022 08:29 AM)J-F Garnier Wrote:  So I would not ask for an equivalent of the DM41X or worst the 41CL.

Well, we are on the opposite side on this one.
For me, the 41CL is by far the best 41 there is.
I get a fast CPU, all the modules ROM images while still being able to use all the physical peripherals.

Of course I just meant the 41CL is far from a simple machine. Using 'worst' was maybe misleading...

Quote:

(11-02-2022 08:29 AM)J-F Garnier Wrote:  Regarding modules, the question was already asked here and the Advantage surely is the obvious choice.
Which other built-in modules would we really need?

Euh ... new modules from Ángel/others, CCD, ZenROM, modules that use QROM like HePaX/RAMBox/others, etc.

Sure there are many interesting modules, but the problem begins when asked to select just a few ones for a general-purpose, stand-alone configuration.

J-F

[agarza]

(11-02-2022 03:50 PM)J-F Garnier Wrote:  

(11-02-2022 02:49 PM)Sylvain Cote Wrote:  Euh ... new modules from Ángel/others, CCD, ZenROM, modules that use QROM like HePaX/RAMBox/others, etc.

Sure there are many interesting modules, but the problem begins when asked to select just a few ones for a general-purpose, stand-alone configuration.

J-F

Exactly! What are the popular general-purpose modules that should be included in the firmware? Other modules could be uploaded in RAM.

[rprosperi]

(11-02-2022 06:48 PM)agarza Wrote:  Exactly! What are the popular general-purpose modules that should be included in the firmware? Other modules could be uploaded in RAM.

Your own thread a few weeks ago discussed which were most common in the past and there were several answers provided. Are you asking about which additional modules, or are you asking which ones are popular and widely used today?

Also, how many 4K modules do you think you can include?

[agarza]

(11-02-2022 08:11 PM)rprosperi Wrote:  Also, how many 4K modules do you think you can include?

I can probably squeeze about 12 4K modules.

[toml_12953]

(10-29-2022 07:58 PM)agarza Wrote:  So, I really wanted the full functionality of the HP41CX for the PX DIY calculators.
But the ATMEGA328 has very limited memory (both flash and ram). Fortunately, there is a relatively new microcontroller from Microchip. Same physical size and thru hole (28 pins) but with lots of ram and flash.

So what's the advantage over the SwissMicros DM41X? (other than cost, of course.) It seems like the DM41X is a better choice if you want to add modules without reflashing the whole thing or if you want to print to an infrared printer.
Also, the DM41X is a portrait format, more like the original calculator.

Now if yours could interface with plotters, floppy drives, printers like the original, that would give it an edge over the SM version.

[Jlouis]

[/quote]
So what's the advantage over the SwissMicros DM41X? (other than cost, of course.)
[/quote]

Cost is just enough for his project to be appreciated (at least for me).

I still haven't bought the DM41 yet. The calculator itself is not cheap and taxes (60%) and shipping cost to my country make it a no priority for me at the moment.

That''s why I m interested in this project.