SUBCART

[tmp]

Thread for SUBCART firmware announcements / bug reports

Differences compared to AVGCART:

---

• More onboard RAM, allowing e.g. expanding Atari to 1088kB (in all scenarios, not only ATR, including 16kB stock Atari 600XL) or provide 4MB AXLON compatible mem expansion (PBI or ECI cable required)
• built-in battery backed RTC with SDX driver
• Optional DAC cable allows stereo POKEY/COVOX emulation (PBI or ECI cable required)

Onboard RAM is slower than the one used in AVGCART which makes filesystem browsing/loading files slightly slower (will be benchmarked).

You need ECI or PBI cable to make use of any extra features. Using it on a modified machine (3rd party internal memory expansion, U1MB) is not recommended and will most likely cause conflicts.

POKEY emulation should be considered beta and will gradually improve with FW updates.

 

Latest firmware:

0010 (changelog)

 

Edited August 13, 2023 by tmp

[+scorpio_ny]

Hi @tmp,

 

I am thinking of getting this cartridge but I have a question: Will it allow an Antic banking scheme (i.e. Compyshop) on the XE computers since HALT is on the ECI?

 

[tmp]

i don't know, sell the idea to me, what games/demos that need compy are worth the effort?

[+scorpio_ny]

No, it is not necessary to include it. I was just curious since the ECI has the HALT signal as opposed to the PBI connector. There does not seem to be a lot of external RAM expansion

tailored to the XE ECI specifically.

[tmp]

i tried to get it working on avgcart last year or so but it wasn't working properly for some reason (some demos had glitches, some didn't) so i just disabled it

i might revisit it one day when i'll feel masochistic but that's not a promise, always make decisions based on existing features, not what people promise you 

[tmp]

i finally made a search benchmark run to figure out how much slower subcart is compared to avgcart, results seem a bit weird to me but i can't find an error in tests

 

methodology: format (fat32) sd card (some 8gb sandisk i had here), unpack latest Homesoft Collection (228 dirs, 4918 files), unpack latest atarionline.pl (tosec named, 5469 dirs, 18040 files) game collection, search for "zybex" (actually "ybex" since i found out that Z key stopped working on this machine, pathetic) in both collections (should traverse through all directories and find some zybex files under Z dir)

 

AVGCART: 2s, 15s

SUBCART: 2s, 16s

 

so basically the same which is confusing because i could swear that early in development i ran a quick test and i feel the "overkill" aol test was in 30-40s range but i'm not complaining

 

for completeness, i ran the same search using the same card on a different multicart, the results were 36s and 272s

Edited August 16, 2023 by tmp

[_The Doctor__]

nevermind 2 different test cases but the result are confusing.

Edited August 16, 2023 by _The Doctor__

[+scorpio_ny]

33 minutes ago, tmp said:

i tried to get it working on avgcart last year or so but it wasn't working properly for some reason (some demos had glitches, some didn't) so i just disabled it

i might revisit it one day when i'll feel masochistic but that's not a promise, always make decisions based on existing features, not what people promise you 

Thank very much for that bit info and thank you for trying! Maybe someday!

[tmp]

.

Edited August 16, 2023 by tmp

[_The Doctor__]

Yes I figured that going back and reading is again, but you are correct the results don't make sense. very odd indeed. maybe renaming moved the file to the beginning of the SD cards wear leveling an it's not at the end any more or some such strange thing?

 

Edited August 16, 2023 by _The Doctor__

[Wilheim]

Just received mine! It rocks!!

 

Would you give support for 2M and 4M Megacarts?

[Zolaerla]

I have a couple questions, cause this looks like exactly what I want!

 

1) Can you use all three extra cables at once (ECI / SIO / DAC)? I want to play with all the features at once.

 

2) Do any configurations allow .ATR files that load a custom RAM-based OS in high memory (such as used by Alternate Reality: The Dungeon) that have their own SIO code? I'd guess the SIO cable version, but wanted to double check.

[tmp]

7 hours ago, Wilheim said:

Just received mine! It rocks!!

 

Would you give support for 2M and 4M Megacarts?

do you have car files for those?

[tmp]

6 hours ago, Zolaerla said:

1) Can you use all three extra cables at once (ECI / SIO / DAC)? I want to play with all the features at once.

of course

6 hours ago, Zolaerla said:

2) Do any configurations allow .ATR files that load a custom RAM-based OS in high memory (such as used by Alternate Reality: The Dungeon) that have their own SIO code? I'd guess the SIO cable version, but wanted to double check.

yes, all three atr handling methods are supported (patched os in ram, using "pbi newdevice" functionality (eci/pbi cable), full sio emulation (sio cable)), when sio cable is connected, the last method is used unless it's overridden via shift-return (i need to add a setting to let user set the preferred method)

[Wilheim]

1 hour ago, tmp said:

do you have car files for those?

I'll pm you with the images, thank you!

[Yellowman]

Hello folks,

a few years ago I built a demo compilation for the 4MB Mega Cart. 
When The!Cart came out later, I split this compilation into two parts as 2MB Mega Cart Roms. 
The!Cart cannot process the 4MB type. Attached are these rom files including header. 
The Mega Cart 4MB is type $39 and the Mega Cart 2MB is type $40. 
Would be nice if it can be implemented in the SUB Cart.

 

By the way, I affectionately call the SUB, Octopus Cart. All these cables are like the arms of an octopus. 
 

Demos are forever.zip

[Wilheim]

The SUBmarine Octopus Cart 😂

[tmp]

On 8/18/2023 at 12:44 PM, Wilheim said:

I'll pm you with the images, thank you!

 

On 8/18/2023 at 4:45 PM, Yellowman said:

Hello folks,

a few years ago I built a demo compilation for the 4MB Mega Cart. 
When The!Cart came out later, I split this compilation into two parts as 2MB Mega Cart Roms. 
The!Cart cannot process the 4MB type. Attached are these rom files including header. 
The Mega Cart 4MB is type $39 and the Mega Cart 2MB is type $40. 
Would be nice if it can be implemented in the SUB Cart.

 

By the way, I affectionately call the SUB, Octopus Cart. All these cables are like the arms of an octopus. 
 

Demos are forever.zip 6.08 MB · 15 downloads

thanks, i'll have a look at next week

[Wilheim]

 

36 minutes ago, tmp said:

 

thanks, i'll have a look at next week

Thank you!

 

another thought it came to my mind: have you considered putting the covox emulation into the audio in SIO pin port? I understand that the SIO cable the audio pin is not present, but who knows, maybe it could be a feature to consider in the future.

[_The Doctor__]

5 hours ago, Wilheim said:

 

Thank you!

 

another thought it came to my mind: have you considered putting the covox emulation into the audio in SIO pin port? I understand that the SIO cable the audio pin is not present, but who knows, maybe it could be a feature to consider in the future.

that could probably be looped back so 800's could have that as well, but since stereo was the goal, the current dongle/pug got it done in any event as you have a right and a left out to your tv/monitor/stereo... as a monaural source a switch might be needed turn it on or off. 8 channel mono sound plus covox actually is a nice thing, and 4+4 and covox stereo is better. Not a bad idea at all!

Edited August 21, 2023 by _The Doctor__

[ndary]

where can i order the SUB CART?

[mimo]

1 hour ago, ndary said:

where can i order the SUB CART?

miscRetro link is in tmp's signature

[Wilheim]

Hi!

 

During the weekend I tried the Das Omen demo, and the music sounds weird on stereo pokey emulation.

 

just to let you all know.

[pseudografx]

SUBCart and AVGCart are currently on sale at miscretro.com if anyone's interested.

Edited August 29, 2023 by pseudografx

[+scorpio_ny]

Thank you for the heads up! Just picked up the Subcart.

Edited August 29, 2023 by scorpio_ny