COCO2 Game Editor for the VIC

Schema · Post by **Schema** » Mon Jan 23, 2006 5:16 pm

I borrowed this cool program from Centallica. Here is the disk image.

http://www.jammingsignal.com/vic20/coco2-vic20.d64

I have no idea why they called this COCO2. It's an "educational game maker" for the VIC20 with 16K expansion. Because of the name, it's hard to find anything about it on the Web.

When you run the COCO2 program, it just freezes. It gets stuck in a loop at $3D7A, not sure what that code is supposed to be doing.

Using VICE

I was able to get the program running by breaking execution and typing G 3D85, which is where it looks like the next chunk of code starts. Maybe one of you 6502 gurus can dig a bit deeper into the problem?

I also have the manual but it's over 100 pages

It seems to be reasonably self expanatory though.

Schema · Post by **Schema** » Mon Jan 23, 2006 5:27 pm

To get it running on a real VIC, type

POKE 15747,240

before typing RUN. This changes the offending BNE to a BEQ. Still no idea why the code has that loop in it though.

Centallica · Post by **Centallica** » Mon Jan 23, 2006 5:28 pm

Leif,

Did you try the cassette that came with it as well, to see if that worked?

I guess it's not a double sided floppy with another version on the other side too

Have you been thinking of playing "Bonks" lately, I sure have

Brian

Schema · Post by **Schema** » Mon Jan 23, 2006 6:04 pm

Unfortunately, the tape gives ?LOAD ERROR and the resulting program is gibberish

I'm fairly certain the tape drive is OK as other tapes load fine.

carlsson · Post by **carlsson** » Tue Jan 24, 2006 5:01 am

Let's see..

Code: Select all

3D7A LDA #$00
3D7C TAY
3D7D STA ($33),Y
3D7F LDA ($33),Y
3D81 AND #$04
3D83 BNE $3D7A

16-bit address at $33-34 is set to point to $9111, or 37137 in decimal. By pulling joystick up, the program starts. You may have to pull a couple of times, since the loop keeps writing zero to that register - is it configured as both input and output at the same time?

Schema · Post by **Schema** » Tue Jan 24, 2006 11:39 am

There's a little insert sheet that talks about plugging in your "Joystick Adaptor" before powering up the VIC. I assumed they meant joystick, but maybe there was a dongle protection system?

carlsson · Post by **carlsson** » Tue Jan 24, 2006 12:47 pm

Not much of a protection if any joystick would work. On the other hand, I've only tried it via emulation, maybe it is much harder to bypass on a real VIC-20.

CurtisP · Post by **CurtisP** » Tue Jan 24, 2006 10:06 pm

Schema wrote:There's a little insert sheet that talks about plugging in your "Joystick Adaptor" before powering up the VIC. I assumed they meant joystick, but maybe there was a dongle protection system?

It was a dongle. I have an original in a box with the dongle somewhere. Never got to use it since I didn't have RAM expansion though.

Sparky · Post by **Sparky** » Fri Jan 27, 2006 7:42 pm

Centallica wrote:Leif,

Did you try the cassette that came with it as well, to see if that worked?

I guess it's not a double sided floppy with another version on the other side too

Have you been thinking of playing "Bonks" lately, I sure have
Brian

there is always time for "Bonks Adventure" hey Schema i thought Centallica had turn to the Dark side when i saw Coco 2 it being a name of a TRS-80/Tandy product

very odd.

Centallica · Post by **Centallica** » Fri Jan 27, 2006 8:43 pm

CurtisP wrote: It was a dongle.

I'd like to know what a "dongle" is personallly

Is it like a dong that gets shaken afterwards

Brian