Robert M

I am looking to sell my VCSp Revision 6 hand-held Atari 2600 made by Ben Heckendorn. In case you never heard of these, it is a custom built from machined plastic and parts. You can learn more about these devices at Ben's Blog. Its a fun little device, but it has its quirks and I so you won't be disappointed let me clearly state all the things that are negative about it. 1. I broke one of the rechargable battery connection pins off. I am sure it is repairable, but not by me. You can still run it off the wall plug. 2. The thumbpad does not work well for diagonal movement. 3. The screen does not display flicker very well at all. So games without flicker (Activision titles and Older Atari titles) look great. Games with lots of flicker, like Ladybug, do not look very good. The flickering sprites become almost invisible. 4. I never used the video out connection on the side of the unit. I don't have the right cable, so I don't know how well it works. 5. There are no difficulty switches. Both switches are hard wired to A (novice). Now whats good about it. 1. Its an awesome piece of custom manufacturing. 2. Its a lot of fun with the right games. 3. Its rare. The serial number on the back is #53, I don't know how many were made in total. I will include a radio shack power supply that provides 7.5 volts with it. I am looking for $175 dollars including shipping within the continental USA, or best offer. I can provide more photos. Is anybody interested?

This might not work for you, but you could use the Reverse character set, and then change the color of all the text on the screen at once by changing the screen background color. You would need to fill in all the unused space on the screen with reversed blank characters to make this work. Another possibility might be to use the Wait command to wait for the raster to reach the bottom line before the border, then switch the video ram to another 1K bank. Use the PRINT command to quickly print into this other RAM which will also write into color RAM. Then switch back to the original Screen RAM before the visible scanlines are drawn again. 5 Print "<HOME>" 10 For J = 0 to 23: REM Loop for each screen line. 20 WAIT <for raster>:POKE <change SCREEN RAM to unused mememory>:PRINT"<color char><40 spaces>":POKE<Switch back to Text video RAM> 30 NEXT 35 REM Don't print to last character of the screen or a scroll will occur. 40 WAIT <for raster>:POKE <change SCREEN RAM to unused mememory>:PRINT"<color char><39 spaces>":POKE<Switch back to Text video RAM> Sorry I didn't provide real memory locations or parameter values, I don't have my reference books handy. Cheers!

I have to agree with Big O. The problem is most likely in the power supply. Either the power supply is under-rated for the six-switch, or somehting is wearing out in the power supply circuit inside the unit. Like a capacitor is going bad. It sounds like the unit is getting enough power to boot, it runs long enough to draw a partial frame, and then the power sags to the point where the processor resets. During the reset, the sagging power comes back the the process repeats.

Thanks!

If we want to make this a cross-game character, I recommend providing multiple resolutions to match different game kernels. 8 high double scanline monochrome/multicolor. 12 high double scanline monochrome/multicolor. 16 high double scanline monochrome/multicolor. 16 high single scanline monochrome/multicolor. 24 high single scanline monochrome/multicolor. 32 high single scanline monochrome/multicolor. With that kind of a library of mixed resolutions it would be easier for homebrewers to pick up and use either as a main character or for cameos. Cheers!

check out post # 177 on page 8 of this thread Excellent! Thanks again.

Where is this video people keep referring to? I can't find it. Thanks

Al, I think you should put a pre-order notice on the front page of the website. I almost missed this post. pre-order coming soon...

I think your best bet is to store the road edges as graphics tables. The entry for each line includes the HMxx shift from the line above, and the width of the stripe. The animation of the color stripes should be done with separate set of tables, or if your kernel has time you may be able to do the color stripes with some sort if parabolic function.

If it is only happening on the last iteration of the loop, are you decrementing Y to -1 and X to 0 so the last pass through the loop Y = $FF which is causing a page boundary crossing?

Hello, I have received many PMs, and I am responding to them in the order received. Some people want to see the screens in action so I am attaching two images of the same screen from Gauntlet taken on each lynx. On the one you can see the stuck red pixels I mentioned. I will be sending out response PMs to everyone who contacted me within the next 24 hours. Thanks! Here is the better looking one: This one has the red dots:

Hello, I am selling my lynx collection. There are two consoles in the collection. One of them is pretty good. The other one has a few red lines on the screen but is playable especially on games that don't have a black background. Most of the games are boxed. You get double copies of the 4 boxed games on the left in the image, and double copies of Gauntlet and a comlynx cable is included. So you can play two player on those games. The padded bags are a little ripped up, but still good for storage. See the image for the game titles and other goodies included. I am looking to sell the whole thing for $135 shipped in the U.S. If you think its worth something else, make an offer. Thanks,

There is the never seen Monogrammed Space Chase from Apollo

Yes, that fixed the problem. Thanks. Will you be updating the download link on the bBasic homepage to link to these newer binaries for OS-X?

Search for ENEMY_MAX_Y in the source for an example. main052.txt Thanks I can't repeat your issue with your source, either. What version of bB are you using? Mac OS-X version dated 2/14/07 12:59. It is the same one as on the bBasic homepage.

Search for ENEMY_MAX_Y in the source for an example. main052.txt Thanks

I think I found a bug with const. When I write something like this: const ENEMY_MAX_Y = 80 player1y = ENEMY_MAX_Y I expected to get the following ASM: lda #ENEMY_MAX_Y sta player1y Instead I get: lda ENEMY_MAX_Y sta player1y So the const value is compiled as the address to read the value from and not the value itself. Is this the correct behavior for bBasic? I can see where if the expression contains a variable added to a constant it would imply I want to index memory from the variable address+constant. So this may be the expected behavior for bBasic. Thanks

Thanks. Is it OK with you if I add an adapted version of this info to the bB page? Sure, information is free. I will be happy to review it for correctness when you are done. Cheers

Pretty cool. So is that a lot faster? It is very fast, and more importantly it always takes the same short amount of time. Whereas a long list of if-then statements takes an variable amount of time to complete. You are correct. Note there are 4 bits one for each direction of the joystick. Those 4 bits make 16 possible combinations. Only 9 of those combinations are valid joystick positions. The other seven are illegal positions like Left and Right at the same time. My example code treats the illegal positions the same as if the joystick is centered which is when the player stands.

This is correct, but you did not include the check of the firebutton... if (SWCHA>=240) && (!joy0fire) then If the reason this works is not clear. It is because the bits that indicate a joystick direction are bits 4-7 in the memory location labeled SWCHA. So the bBasic code joy0right is the same as code SWCHA{7}=0, joy0left == SWCHA{6}=0, joy0down == SWCHA{5}=0, and joy0up == SWCHA{4}=0 The bits 4-7 if they were used to represent a number would equal 16+32+64+128 = 240. The bits are set to zero if the joystick is pushed in that direction. So if the joystick is cnentered all 4 bits are set equalling 240. If the joystick is pressed in any direction that bit will be zero and the value in SWCHA will be less than 240. The joystick firebutton is from a different register than SWCHA. Personally I think to be quickest in your code you need to get rid of if-then statements for joysticks all together. You can use the ON GOTO statement to jump directly to the correct code for each legal and illegal joystick position. Here is a snippet from my shooter game: if joy0fire then Fire temp1 = SWCHA / 16 rem RLDU = 0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1111 on temp1 goto Stnd Stnd Stnd Stnd Stnd GoRD GoRU GoR Stnd GoLD GoLU GoL Stnd GoD GoU Stnd Fire rem -- Player shoots if playerShotYpos then ShotBusy playerShotXpos = playerXpos + 2 playerShotYpos = 21 ShotBusy player0x = playerXpos REFP0 = playerStatus goto PlayerKneel Stnd rem -- Player stands still. player0x = playerXpos playerStatus{0} = 0 REFP0 = playerStatus goto PlayerStand GoD GoU rem -- Player kneels and shows shield if avalable. player0x = playerXpos REFP0 = playerStatus if shieldStrength then playerStatus{0} = 1 : goto PlayerKneel playerStatus{0} = 0 goto PlayerStand GoR GoRD GoRU rem -- Move player to Right. if playerXpos < 136 then playerXpos = playerXpos + 1 player0x = playerXpos playerStatus{3} = 0 playerStatus{0} = 0 REFP0 = playerStatus goto AnimatePlayer GoL GoLD GoLU rem -- Move player to Left. if playerXpos > 16 then playerXpos = playerXpos - 1 player0x = playerXpos playerStatus{3} = 1 playerStatus{0} = 0 REFP0 = playerStatus goto AnimatePlayer

There will be ground enemies. Things that crawl down the walls and across the floor, or emerge from the floor holes. I am leaning towards making the current slide move into an attack move against ground enemies. Does that sound like a good idea? Thanks everyone for the kudos.

Yes, and/or some enemies will require a minimum power level to even damage them. That's a possibility. Definitely. Thanks.

I think the definitive source for the baseline features of the VCS is given in the Stella Programmers Guide written in 1979. It lists all the features Atari knew the system would support at console launch. Additional programming tricks that added features were then discovered over the years. Rob stella.pdf

I have a lightly used programmer somewhere in my basement I am willing to sell. I will try to dig it out and see how it looks.

Good stuff! keep going.