RCA Studio II GOLD MINE! An interview with the Studio 2 Production Manager!

[slydc]

Hi Marcel,

 

Thanks very much for all the fixes you've made and they all work flawlessly on Emma02, now just need to test it

with the multicart on a Studio II.

 

About the Chip8.bin for the Studio II: Indeed that was fun and i still grateful that you did this as i've always wanted to play

Chip-8 games on a Studio II, and now we can play more than 100 Chip-8 Games and there still al least 200 Chip-8 games

that haven't been saved/typed-in so this will expand the game library by so much. And you also ported it to the Elf2K ?

Is there anything you can't do ?! LOL!!

 

As for other programs that has the "shift" problem, there is "Blinky" that when you try it, the maze is gibberish. And the

author (Thomas Daley) of the emulator "Kiwi8" has made a list of games/programs that has mostly the same problem or

have other "glitches". You can check his list/report here: https://github.com/tomdaley92/kiwi-8/issues/9

 

 

 

 

 

[etxmato]

Hi sly DC,

 

Ok, we have a bit of a problem here....

 

I see that some of the games in your archive are different form the ones I have in the Emma 02 archive. Like Blinky, Connect 4, Tic Tac Toe, Space Invaders etc. All of 'my' versions work fine, the ones you have don't. I was sure my versions were the original but thought I check on David's site and to my surprise mine are NOT the originals, yours are :). So someone has already fixed some of these, not sure who....

 

Now the question is what we should fix, should we have multiple versions of the chip8 games or correct the chip8 code on the VIP, Studio II, Elf 2K and Elf?

 

I did a test with the chip8 on the VIP and have made a version to have the same load_store-quirk as on the page linked by you above. With this fix I could run the Connect 4 and Star demo from your archive correctly. 

 

It is all a bit messy, unfortunate that the Chip8 versions deviated from each other over the years. Of course my opinion is that the original VIP is the 'correct' one but at the same time we have a lot of code now that won't run on that version.... so maybe creating multiple chip8 interpreters with the quirk fixes is better?

 

Opinions from anyone?

 

Cheers, Marcel.

[etxmato]

Looked into the shift_quirk, that is actually not that easy to do in the chip8 interpreters. The code is the same for all/multiple 8XY. commands so it would alter other commands as well. So for the moment I will leave that idea. Also the shift command is rather easily fixed in the game code and a fix would run on both type of interpreters.

 

So maybe an idea is to 'fix' the shift errors in the games and have a load_store_quirk version for the different interpreters (VIP, Elf, Studio II and maybe the Elf2K).

 

Cheers, Marcel.

[slydc]

Hi Marcel,

 

The best is trying to "fix" the games that have "quirks" and to tell apart an original game or a fixed one, we should put a "fix"

notification in the identification like this: Blitz (fix)(David Winter)(199x).ch8

 

If the "load_store_quirk" can't be fixed in the games, then make a new Chip-8 interpreter with the notification: Chip-8 (VIP)(load_store_fix).bin

so this way we will know that this interpreter fixes the "load_store_quirk" problem. And i completely agree with you, Chip-8 interpreters are

deviating from each others over time....sigh.

 

Oh and putting in each games that needs the "load_store_quirk" interpreter in the (how-to-play) text manual will also be very helpful before

too many persons ask why (specific game) doesn't work.

 

And if anyone wants to know how many different interpreters already exists, go here (and go crazy):

https://gist.github.com/tobiasvl/a0e43bdcd64d9ef6be35f5c67fcff0dd

 

[etxmato]

Hi Sly DC & others,

 

Some findings and fixes attached. Not all of these were done by me but for some reason I already had some fixed code. Some others I corrected, all shortly described in matching txt files. The only load_store_quirk program (that I know of) that I don't have a fix for is the stars demo. 

 

I also found some games with wrong type or in the wrong folder:

 

The following code is Super-chip8:

Super Square (tann)(2014).ch8 (is in the chip8 folder)

Traffic (by Christian Kosman)(2018).sc8 (is in the chip8 folder)

Hires Blinky (by Michael Wales)(2015).ch8 (is in the high res folder but is not a high res game)

 

The following code is hybrid not chip8X:

Bingo [Andrew Modla] (hybrid).c8x
Blackjack [Andrew Modla] (hybrid).c8x
Message Center [Andrew Modla] (hybrid).c8x
Pinball [Andrew Modla] (hybrid).c8x
Video Display Draw [TCNJ S.572.2].c8x
Video Display Drawing Game [Joseph Weisbecker] (hybrid).c8x
 

Chip8X is the colour / sound version whereas hybrid is Chip8 and 1802 code combined.

 

Last the following games gave some problem or I don't really 'get them', if anyone has more info please comment:

 

Death Star vs Yoda (by TodPunk)(2018).ch8
- Hitting the Y causes a crash

 

Deep8 (by John Earnest)(2014).ch8
- I have seen this working once; but most times there is no possibility to 'do' anything before the ship is blown up.

 

Mysterious (by Guillaume Desquesnes)(2019).ch8
- F key starts something but I just see rubish on the screen on subsequent key presses

 

Snafu (Shendo)(2010).ch8
- looks like nothing moves the snake

 

Snake (by Daniel Jianoran)(2018).ch8
- Looks like chip 8 code is using RAM 0-0x200 where the VIP interpreter is located and as such crashes the game

 

SNEK (by glitchland)(2020).ch8
- looks like nothing moves the snake

 

Sokoban1 (by Daniel Jianoran)(2018).ch8
- Looks like chip 8 code is using RAM 0-0x200 where the VIP interpreter is located.

 

Space Intercept (fix)(Joseph Weisbecker)(1978).ch8
- Does anyone know what was fixed, I thought the original game was 'ok'?

 

Super Block (by Joshua Barretto)(2019).ch8
- key 5 and 6 do something but I don't really get it

 

Tank! (by RectusSA)(2018).ch8
- Key E fires but screen doesn't get cleared after shot?

 

Tick-Tack-Toe (fix)(by Joseph Weisbecker)(1977)

- Does anyone know what was fixed, I thought the original game was 'ok'?

 

Warshaws Revenge (by Ethan Pini)(2019).ch8
- Some graphics look strange? Not sure how the game works either

 

X-Ray (Rand Miller)(1980).ch8
- looks like it gets into an endless loop after a few key presses

 

Boot-128 (hybrid).c8x
- No clue what this does

 

I also had problems with some of the demos but haven't listed the errors (as yet).

 

Cheers, Marcel.

Animal Race (fix)[Brian Astle].ch8 Animal Race (fix)[Brian Astle].txt Astro Dodge (fix)[Revival Studios, 2008].ch8 Astro Dodge (fix)[Revival Studios, 2008].txt Blinky (fix)[Hans Christian Egeberg, 1991].ch8 Blinky (fix)[Hans Christian Egeberg, 1991].txt BMP Viewer - Andnxor (fix)(by And!Xor Team)(2017).ch8 BMP Viewer - Andnxor (fix)(by And!Xor Team)(2017).txt BMP Viewer - Hello (C8 example) (fix)[Hap, 2005].ch8 BMP Viewer - Hello (C8 example) (fix)[Hap, 2005].txt Connect 4 (fix)[David Winter].ch8 Connect 4 (fix)[David Winter].txt Hidden (fix)[David Winter, 1996].ch8 Hidden (fix)[David Winter, 1996].txt LabVIEW Splash Screen (fix)(by Richard James Lewis)(2019).ch8 LabVIEW Splash Screen (fix)(by Richard James Lewis)(2019).txt Lainchain (fix)(by Ashton Harding)(2018).ch8 Lainchain (fix)(by Ashton Harding)(2018).txt Lombat Lombat Asoy! (fix)(by Razka173 Team)(2018).ch8 Lombat Lombat Asoy! (fix)(by Razka173 Team)(2018).txt Loose Cannon (fix)(demo).ch8 Loose Cannon (fix)(demo).txt SierpChaos (fix)(by Marco Varesio)(2015).ch8 SierpChaos (fix)(by Marco Varesio)(2015).txt Tic-Tac-Toe (fix)[David Winter].ch8 Tic-Tac-Toe (fix)[David Winter].txt

[slydc]

Hi Marcel!

 

Looks like you were pretty occupied. First, thank you so much for all the "fixed" programs and with text which

described what was the problem in the program. I'll add these info with the proper manual program (if exists).

 

I have made the corrections:

 

The following code is Super-chip8:

Super Square (tann)(2014).ch8 (is in the chip8 folder)

Traffic (by Christian Kosman)(2018).sc8 (is in the chip8 folder)

Hires Blinky (by Michael Wales)(2015).ch8 (is in the high res folder but is not a high res game)

 

## Those are in the proper folder except for "Hires Blinky" as i have find out it is exactly the same version

as the one made by Hans Christian Egeberg. So have to delete this one. ##

 

The following code is hybrid not chip8X:

Bingo [Andrew Modla] (hybrid).c8x
Blackjack [Andrew Modla] (hybrid).c8x
Message Center [Andrew Modla] (hybrid).c8x
Pinball [Andrew Modla] (hybrid).c8x
Video Display Draw [TCNJ S.572.2].c8x
Video Display Drawing Game [Joseph Weisbecker] (hybrid).c8x

 

## All in their respective folder now and change their extension also: ".hc8" (for Hybrid Chip8) and

".c8h" are for Hires Chip-8 (64x64) and put those in the "various" tab. ##

 

Last the following games gave some problem or I don't really 'get them', if anyone has more info please comment:

 

## There is two i can't explain for now (the two already "fix") and the rest, i have made manuals on how to play

them as clearly as possible. ##

 

So here's the manuals for 12 of the games listed above, have fun all!

 

P.S.: The Snake.png is what is supposed to look like from the emulator of the same author. Tried it in Emma02, was able to

play with it but it crashes after pressing a few buttons.

boot-128.txt Death Star vs Yoda.txt Deep8.txt Mysterious.txt snafu.txt snake - Daniel Jianoran.txt Snek.txt Sokoban1 - Daniel Jianoran.txt Super Block.txt Tank!.txt Warshaws Revenge.txt X-Ray.txt

Edited September 10, 2020 by slydc

[etxmato]

Hi Sly DC,

 

Are you sure the Highres Blinky is the same as the original? I did see a 00FF code in there somewhere which is code for switching to high res in super-chip8....

 

Thanks for the game explanations, that helped for a few:

Death Star vs Yoda - I added a fix so it doesn't crash in the end

Mysterious - I added a fix to display numbers correct on the VIP

X-Ray - found some typos when I compared the first 512 bytes with the manual, now it runs better. There might be more typos.

Also note X-Ray is a hybrid! it includes 1802 code and as such probably won't run on Chip8 emulators.

 

These 3 fixes are attached....

 

Others:

Deep8, snafu, super block - all indeed run 'ok' with your manual... super block is a bit slow on the VIP and the ''player' looks slightly different then on the chip8 emulator online. Might also be due to speed, not sure.

 

Snake and Sokoban1 are as far as I can figure out not complying to chip8 code. They store data over 0-0x200 which crashes the VIP. When I try to correct that and also correct a shift error they still don't run properly. I also think Snek and Tank! have bugs or don't comply to chip8 code. Warhaws Revenge might be 'ok', but still not sure what the end game is.... 

 

I will not include the games which don't run.

 

Anyway, thanks a mill for all the work you must have put in to try and collect all this :).

 

Cheers, Marcel. 

 

X-Ray (fix)(Rand Miller)(1980).txt X-Ray (fix)(Rand Miller)(1980).ch8 Mysterious (fix)(by Guillaume Desquesnes)(2019).txt Mysterious (fix)(by Guillaume Desquesnes)(2019).ch8 Death Star vs Yoda (fix)(by TodPunk)(2018).txt Death Star vs Yoda (fix)(by TodPunk)(2018).ch8

[slydc]

Hi Marcel!

 

Yes i am very sure that Highres Blinky is the same as the original as i have compared both programs with a hex compare program like this:

 

 

No problem for the explanations of some games, glad i can help.

 

I also updated the Chip-8 excel sheet with these new fixes and problems, thanks very much!

 

For the four games (Snake, Sokoban1, Snek and Tank!), i have compared them with 4 emulator (including yours of course!)

 

* Snake: In Octo and Emma 02 it doesn't work but with Fish 'N Chip it works and with Kiwi8 it works only if the Load/Store & Shift Quirks are enabled.

 

* Sokoban1: Same results as for the Snake game.

 

* Snek: in Octo, it doesn't move and in Emma 02 & Kiwi8, it "bugs". But it works with Fish 'N Chip.

 

* Tank!: This one works with all four emulators but is very slow with Fish N Chip and Kiwi8. I tried it with Emma 02

and works like a charm once you configured the hex keypad like this:

 

1-2-3-4        1-2-3-C

Q-W-E-R       4-5-6-D

A-S-D-F        7-8-9-E

Z-X-C-V        A-0-B-F

 

And with the PNG manual sheet, i played a few rounds without any problems.

 

As for the other three games, i'll put them in a folder called "not-properly-working".

 

The "Chip-8 Database" took at least 5 years to gather all the programs and info and there's still a lot more to be done.

Hopefully, all programs will be in a "rom" format with their proper manual, screenshots and hex list to all to enjoy (gamers,

programmers, etc) for many years to come.

 

 

Edited September 14, 2020 by slydc

[etxmato]

Hi

 

Maybe slightly off topic but when I looked at Sly DCs Chip8 archive and the links he provided in previous posts, I got interested (again) in super-chip. Way back I had seen different super and mega chip descriptions but I had dismissed them for the 1802 machines, mainly due to higher resolutions. Now I noticed super-chip uses the same resolution as the chip10 which is running on a HW modified VIP. So I thought hmm, couldn't we run super-chip on that same modified VIP?

 

and....? Yes!

 

 

Super-chip Blinky running on a very early version of my new 1802 super-chip interpreter :).

 

So far this is the only game I got running, I did have to make the shift_quirk fixes which were done in the chip8 version but than it does run. I might be able to fix those in this interpreter as I have made some more 'space' available. It will also need a VIP with 8K due to the larger interpreter size and 1K video memory which would otherwise leave less than 2K for games. 

 

I have the down scroll working but it is way too slow for any game play, left and right scroll is not implemented and just scrolling 4 pixels is going to be impossible on the 1802 due to speed. 8 pixels would be possible but also as slow as the down scroll. So we'll have some speed problems.... but it was fun to see Super Blinky come to live on the VIP.

 

When I have this running, I also intend to see if I can port it to the Studio IV. The IV has the same resolution so it should be doable.

 

To be continued....

 

Cheers, Marcel.

[slydc]

Hi folks!

 

Sorry if me and Marcel has been going a bit "off-topic" with the Chip-8 stuffs and all, but Chip-8 is related to the RCA Studio II/III since the

COSMAC VIP is almost the same hardware as the Studio II, the big difference between the two is the tape interface and ram. The Studio II

can be easily be modified into a VIP with ram upgrade and others little mods. And with Flip's multicart, we can even add Chip-8 games to play

them (but not all) on a Studio II without modding it, so this expands the game library to more than 200 games  as there is about 200 more

Chip-8 games not typed from various newsletters/magazines.

 

I have finally made mini-manuals, especially which buttons does what, for each Chip-8 games (existing in a ROM-type format) which is 163

as of today (Sept.19, 2020). I'm not sure if every mini-manual is exact as i've mostly copy-pasted descriptions of the games when they had one.

There is only two games that the manuals aren't finished: Chesmac (no manual right now) and Space Explorer.

 

So if anyone wants to check all 163 Chip-8 games works or not with Flip's multicart, be my guess as i'm trying to concentrate that each games

as been correctly identified (title, author, year) and have their manual and later on screenshots.

 

The Chip-8 Database will be updated during this week-end. Have fun!

[slydc]

Hi Marcel,

 

Super Chip8 on the VIP ??  I knew it was possible as the specs for the CDP1861 (also CDP1862 & CDP1864) can go up to 128x64 but needs

more RAM (1k more i think?). With Eproms now, why bother to upload a game or program into RAM when you just need to add a port to install

ROM carts so this will leave the RAM for higher resolution, colors (also this one needs 1k extra RAM), and variables as the rest of the game/program

can be stored into ROM (or Flip's multicart).

 

Maybe ROMS (Eproms) can be inserted by the VIP expansion port ? (haven't checked that out yet). Anyway, i am amazed that you have succeeded

to adapt the Super Chip-8 to the VIP, even if it's only one game but the first step is done! Can't wait to see the development for the VIP S-Chip, so

hats off to you Marcel!

[etxmato]

Hi Sly DC,

 

Correct, 1K RAM is needed for video RAM in the 128x64 resolution, whereas the lower res only needs 256 bytes of video RAM.

Some of the chip8 games do need to be running in RAM, that was one of the issues I had when porting to the Studio II....

 

Two S-CHIP games tested 'ok' now on the VIP, most still have some strange graphics here and there. Possible caused by my code or incompatibilities like the shift and load quirks from chip8.... will continue tomorrow :).

 

Cheers, Marcel.

[djones60]

4 hours ago, slydc said:

Hi folks!

 

Sorry if me and Marcel has been going a bit "off-topic" with the Chip-8 stuffs and all, but Chip-8 is related to the RCA Studio II/III since the

COSMAC VIP is almost the same hardware as the Studio II, the big difference between the two is the tape interface and ram. The Studio II

can be easily be modified into a VIP with ram upgrade and others little mods. And with Flip's multicart, we can even add Chip-8 games to play

them (but not all) on a Studio II without modding it, so this expands the game library to more than 200 games  as there is about 200 more

Chip-8 games not typed from various newsletters/magazines.

 

I have finally made mini-manuals, especially which buttons does what, for each Chip-8 games (existing in a ROM-type format) which is 163

as of today (Sept.19, 2020). I'm not sure if every mini-manual is exact as i've mostly copy-pasted descriptions of the games when they had one.

There is only two games that the manuals aren't finished: Chesmac (no manual right now) and Space Explorer.

 

So if anyone wants to check all 163 Chip-8 games works or not with Flip's multicart, be my guess as i'm trying to concentrate that each games

as been correctly identified (title, author, year) and have their manual and later on screenshots.

 

The Chip-8 Database will be updated during this week-end. Have fun!

I am mostly a lurker and follow along with the discussions.  But the comment about the Studio II being almost the same as a VIP got my attention.  Has anyone documented the mods needed to turn a Studio II into a VIP?  I have a broken one in addition to my good one with the flash cart.  I'd be interested in getting the broken one working and converted into a VIP.

 

Thanks

David

[RayXambeR]

 

All recent news concerning Chip-8 are great! Good work, specially Sylvain!

I am posting here instead of Market place, but I can cancel this post if needed, no worry.

I have one Hanimex MPT-02 complete in box for trade (even with polystyrenes and extra-joystick adapters). I have some games, also for trade (see on photos: star wars is not in a good shape, but it is Star Wars!).

Interesting to trade specifically against a RCA Studio II, in box too.

I also have one loose Hanimex MPT-02 system. Could consider another trade for that (not only on MPT-02 systems).

I am looking for S2 games too (except: Baseball, Blackjack, SpaceWar and Tennis/Squash)

I could also be interested in other clones like Sheen, Apollo or Mustang (and games also) or on other systems (I am looking for Basic on Super cassette vision for example, etc.)

 

[Blazing Lazers]

18 hours ago, RayXambeR said:

 

All recent news concerning Chip-8 are great! Good work, specially Sylvain!

I am posting here instead of Market place, but I can cancel this post if needed, no worry.

I have one Hanimex MPT-02 complete in box for trade (even with polystyrenes and extra-joystick adapters). I have some games, also for trade (see on photos: star wars is not in a good shape, but it is Star Wars!).

Interesting to trade specifically against a RCA Studio II, in box too.

I also have one loose Hanimex MPT-02 system. Could consider another trade for that (not only on MPT-02 systems).

I am looking for S2 games too (except: Baseball, Blackjack, SpaceWar and Tennis/Squash)

I could also be interested in other clones like Sheen, Apollo or Mustang (and games also) or on other systems (I am looking for Basic on Super cassette vision for example, etc.)

 

PM sent.

[etxmato]

Hi there,  

 

Maybe slightly off topic but I finally released Emma 02 V1.37 with my VIP and Studio IV Super-chip interpreter, both would need modifications to run on real machines, i.e. high resolution mod on the VIP and different memory configuration on the Studio IV.

 

Runs on windows, linux and OSX but unfortunately NOT on Big Sur at the moment.

 

For more details see the change log and if you like to give it a spin use the download page.

 

Comments, bug reports or other are welcome as always.

 

Cheers, Marcel.

[ubersaurus]

The new Emma02 also has functioning Tiny BASIC for the Studio IV! I spent a week at Hagley Library on a grant last month and found the source code (among other things) and passed it along to Marcel. So glad to see it up and running again!

[RayXambeR]

I have scanned the manual of the Hanimex MPT-02 system. It is in French language and in very good quality. Don't know if it is has already been saved but I think it is better to do things like that twice than never!

Enjoy!

 

 

[slydc]

7 hours ago, RayXambeR said:

I have scanned the manual of the Hanimex MPT-02 system. It is in French language and in very good quality. Don't know if it is has already been saved but I think it is better to do things like that twice than never!

Enjoy!

 

Merci beaucoup! Et le manuel en Français n'a jamais été sauvegarder (à part maintenant)

[ubersaurus]

Just a bit of an update from the research side of things: First, I received a Hagley research grant last year and spent a week in Delaware going over their paper archives. I didn't finish getting through all the folders and boxes that I wanted, but it was an informative visit - I found some previously unknown and unscanned 1802-based newsletters (featuring some VIP programs), the source code to Studio IV's version of BASIC that has since been implemented into Emma02, the source code to a LINC Pong game from the 60s, and a bunch of other stuff. Ended up doing a twitter thread of some highlights: 

 

Secondly, Hagley digitized some of the materials I asked about while I was up there and the folks were inspired to set up a Hagley Computing Collection digital page to collate them. Highlights include test footage of a VideoDisc adventure game demonstration, the VIP Game Manual II, photos of RCA's 1967 pool computer game and some cool stuff on the Spectra 70 (also a breakdown of Joe Weisbecker's Tic-Tac-Toe playing computer he build in the mid-50s):

https://digital.hagley.org/islandora/object/islandora:2632679

 

And third, I just received an oral history grant through Hagley to interview folks involved with RCA's computer and video game work! Currently reaching out to folks I'd talked to previously by email to see if they'd like to do an oral interview, and to folks I'd spoken to over the phone to see if they'd be willing to have those interviews sent along to Hagley to add to their RCA archive. With luck, maybe this'll shake loose some of the folks who seem to have stubbornly kept a low profile.

 

I should add that there is also renewed interest in game preservation circles to get type-in programs for all kinds of platforms input and saved so they can be ran on actual hardware or emulators; I may give a shot at doing so for some VIP stuff myself but I think it's a worthy effort all-round for RCA's games. There's some type-in code listings for FRED and VIP at Hagley even beyond what's in the game manuals and newsletters...

[carlsson]

Heh. Perhaps one should dig into the Studio IV BASIC through the Emma02 emulator and make an entry for the BASIC 10Liners contest going on right now?

[carlsson]

Btw, I downloaded the latest version of Emma02 and tried the Tiny BASIC in RCA Studio IV. From what I could find, it is slower than an amputated tortoise. There was a discussion in the Intellivision part of the forum about how slow the ECS BASIC is (compared to all real computers and video games trying to implement BASIC). I found that the emulated Studio IV runs even slower, down to 1/3 of the speed of the Intellivision ECS or 1/13 of the speed of Comx BASIC. Yet the emulator says that the Studio IV would be clocked at 3.58 MHz.

 

Furthermore, I compared with the Cosmac VIP II which also seems to have a kind of Tiny BASIC? It is clocked at half the frequency of the Studio IV, but runs the same benchmark 5 times faster (and has a more advanced BASIC syntax). Maybe I'm mixing apples and oranges, but it would seem that doubling the clock frequency on the VIP II would have its BASIC run up to 10 times faster than the Studio IV. The CPU is the same, but possibly rest of the system, RAM addressing, video system traps etc would be different.

 

Perhaps though Tiny BASIC isn't the intended programming environment for this console, rather ST4 or pure machine code.

[carlsson]

Also I wonder if there is any documentation that matches this version of Tiny BASIC. I understand that it is similar to the VIP BASIC, whether that is a subset of VP-701 Floating Point BASIC 2.2. By digging through the ROM binaries, I compiled what I believe is the command set.

 

These would behave like you expect all BASICs to, nothing to remark:

GOTO, GOSUB, IF .. THEN, PRINT, RUN, REM, RETURN, NEW, INPUT, SAVE, LIST, LOAD, LET, END

 

These seem to be more unique:

COLOR n : Changes background color in the range 0-7

CLS : Clears screen

TVON : Enables TV screen

TVOFF : Disables TV screen

 

PT=xx..xx : Defines an image 8 pixels x N rows? E.g. PT=FF818181FF would define a square that is 8x5 pixels.

SHOW x,y : Display the defined graphic at position x,y

HIT : Variable that will tell if any existing pixels were hit when the graphic was drawn. All graphics seem to be drawn in XOR mode?

 

GOKEY : Jumps to a line where it waits for a keypress (exit with GOTO back to the program, not RETURN?)

KEY : Variable that contains the value of the last pressed key

KEY doesn't seem to change by itself, only through GOKEY.

At least it seems that 10 GOKEY 10 will read the keyboard and then move on.

 

RND : Random number between 0 and 255 ?

ABS : Absolute value

MEM : Number of bytes left

 

There seem to be variables/functions TI, TO and FQ as well, but I don't know what they do or how they work. Something with sound? (Tone, Freq)

 

At least there are no FOR .. NEXT statements in this one, unlike the VP-701 which is a far more feature rich environment.

Edited February 16, 2021 by carlsson

[etxmato]

Hi Anders,

 

Yes the Studio IV BASIC is rather slow. One reason for it being slow is that it is written in a pseudo code language, similar set-up as the Chip8. The same BASIC was released for the VIP as the VP700 Tiny BASIC. Both use the same pseudo code (more or less) but interpreters have some larger differences. So the fact that it is not really coded in 1802 code makes it that much slower.

 

Floating Point BASIC 2.2 (or VP701 BASIC) as running in Emma 02 on the VIP II is a completely different BASIC and is more related to COMX BASIC or the Quest BASICs. So purely coded in machine code.

 

The VIP VP700 BASIC uses a lower resolution compared to the Studio IV. But as you say the Studio runs on a faster CPU clock so I would still expect the Studio one to be faster than the VIP VP700. Didn't check or test that.

 

I'm not sure which version you tested. But note that the '2020' versions use my code for the interpreter, i.e. I took the VP700 interpreter and adapted that to the Studio IV HW and higher resolution. This as we did not have a copy of the Studio IV Interpreter code, we just had the pseudo code part. 

 

A few months later Kevin found us a copy of the original interpreter code which I included as 'am4kbas 1978.bin'. I looked thru both interpreters a bit and of course they differ. Possibly my code is slower, I did not test this theory :).

 

Also the Studio IV or the ST IV BASIC were never released, maybe because RCA came to the same conclusion as you :).

 

Cheers, Marcel.

 

 

[carlsson]

What I found out is that the 1978 interpreter runs roughly 33% faster than your 2020 interpreter in PAL mode, but in NTSC mode they all seem to run equally fast?

 

At first I ran this little program:

 

5 LET A=0

10 LET I=1

20 LET A=A+I

30 LET A=A*I

35 LET A=A/I

40 LET I=I+1

45 IF I<1000 THEN 20

50 PRINT A

 

I hand timed it to run in about 995 seconds in PAL mode using your 2020 interpreter.

 

I changed the conditional on line 45 to only run 10 iterations instead of 1000 and got the following, very much hand timed results:

 

1978 version: about 6 seconds (in both NTSC and PAL modes)

2020 version NTSC: about 6 seconds (with the emulator set to NTSC)

2020 version PAL: about 9 seconds (with the emulator set to PAL)

2020 version 32K PAL: about 9 seconds (ditto)

 

Exactly why your interpreter on NTSC would be that much faster, I don't know but the old interpreter as I wrote above, had no change in speed.

 

So what does TI, TO and FQ possibly do, and are there more to this? Are there docs for the VP700 Tiny BASIC? I ended up on this site which has a lot of documents, but I didn't find what I think I am looking for.