tep392

How about I promise there will be no delay due to checking for the XBOARD. Can we stop this nonsense now?

I totally understand being upset about all the delay's but they have nothing to do with the inner working of the BIOS or the XBOARD. The current design allows for the BIOS to be re-flashed in the field, so it doesn't even need to have every bell and wisitle implemented before shipment. It just needs all the key features in place and sufficiently tested. The key activities right now are getting the latest prototype's built and into peoples hands for testing.

Trying to implement stereo with XBOARD and XM would be feature creep and is not something I would support. But adding some simple code to the BIOS to detect and handle the XBOARD scenerio is trivial and would have zero real impact on XM delivery. I'm not an asshole who is going to say f-you to someone who might plug an XM into an XBOARD equipped 7800 that they might not even know has it. Especially when it is trivial to prevent the problem in the first place.

I have a bare board, schematic and JEDEC file for the PLD, so it would be super easy. Finding the creator to get permission would definitely be be the hard part. I'm not sure it would be worth cloning though because it has some compatibility issue. It only works on one of my two 7800's.

Kind of funny that you are only now able to hear the music you did on the real deal.

My idea was for the BIOS to check for the XBOARD and then disable any conflicting features to avoid possibility of hardware damage. Maybe even pop up a message to let the person know, just in case they have and XBOARD machine and don't realize it. I know there aren't many out there, but at least 50 were sold, so there's bound to be a few of them.

I can't speak to the BIOS because it's not mine. That's all I know about it. I was working on one at one point so put a bit of thought into it. There are issues with trying to use the XBOARD and XM together due to them using the same address. The intention was to make them interchangable for POKEY support, not to work together in a stereo configuration. My user name would only make sense to one of my fraternity brothers. TEP = Tau Epsilon Phi. I was member# 392 at my chapter.

I checked with Curt about a week ago and learned that he has received 4 boards with the latest design and has started to build them. This happened just recently.

Use a voltmeter to check the voltage level on pin 3 goes from 5V to 0V when you press the power switch. I don't recommend doing continuity test on populated boards because it applies a voltage to do the check and you could damage an IC this way. I killed a POKEY doing continuity tests on a Ballblazer cart once. Stick to voltage level measurements when possible.

the1hatman has sent me several shipments of boxed commons to help me get my Intellivision collection going. He's a very generous fellow and I can highly recommend him.

https://fccid.io/document.php?id=3588645 There's some posts in the Genesis thread. http://atariage.com/forums/topic/266499-new-genesis-flashback/page-15?do=findComment&comment=3910978

I have an Antonia 4MB RAM upgrade currently installed in my 800XL that I want to sell or trade. Price is $50 + shipping. If you want a trade, I"m looking for Floppy s/w, preferably boxed, and other hardware upgrades for my 800, 800xl or floppy drives. I could use a Happy Enhancement for my 1050. Here's some photo's of it installed in my machine. Here's a link with information on the upgrade. I've never had any problems with it and it works perfectly. It provides 4MB of RAM that can be configured in various configurations plus 8 OS slots and 8 8k language slots. http://atariage.com/forums/topic/249405-new-4mb-ram-expansion/?do=findComment&comment=3446340 Perry

Cool. I misunderstood your post.

Bummer I won't be able to play the 128k version on my 800XL with Antonia 4mb due to the LAX opcode.

I happened to find one last month at my Target, which never has them in stock so I grabbed it for myself. I initially thought I might just resell it, but after doing the same math in my head, realized it just wouldn't be worth the time and effort. So it's attached to my TV now.

Take a look at this map for the ramp screen. To do this in indirect mode (character mapped), I need to have a bunch of horizontally pre-shifted girders defined in the font to make each of these characters. Add even more characters to the font because of all the segments that have ladders on them. To make it worse, maria is spending a ton of time drawing blank characters. By using direct mode, I could theoretically have a single girder segment in my font and position copies of it at any x and y position as a sprite. I'll actually be making one long segment in the font, as highlighted at the bottom of the screen. I can put copies of that segment at any x and y position with whatever length is needed. Using direct objects, instead of character mapped, might be a good option for Delta Space Arena.

My current plan for D2K is to build the screen with sprites. Girders can be made with sprites up to 31 bytes wide. There is a ton of blank space in the Donkey Kong screens and using character mapped graphics wastes a lot of Maria time fetching and drawing blank characters. By using sprites in a smart manner, I can put more animated objects in a zone without resorting to flicker. It will actually give me more font space as well because the Ramp screen in character mode requires girder/ladder characters drawn at 8 different vertical positions. Character map mode was going to require 112 characters in the font just for the girders and ladders. Another plus is reducing overall Maria cycles, leaving more CPU cycles for the game code. The downside is that my display list is going to use a lot of RAM, but I should still be ok with the base 4k.

I think boxed commons would be of interest to people like myself who have small collections. But to help keep shipping under control, they should probably be limited to pristine copies.

I don't know what "attacks" and "real leads" mean, but my opinion is awesome.

I sent a DK PK cart to Protestari in Canada but it decided to take a short vacation in Malaysia. Still managed to get there in 20 days.

Could the program be modified to have the center rows of that large sprite point to a dma hole?

I have another idea. Since I'm using holey DMA, I could set the address of the unused DL header to point at a hole, which would abort DMA reading the graphics.

I think this is correct and happens as the line buffer is being written to, so graphics data has already been read. Pixel data above 159 are thrown out. I found a paper on a 7800 FPGA development project that indicates this is the case.

I'm sure Maria would still read the blank sprite as well. I'm wondering if it still reads the sprite data when X>160. The Maria docs that I've seen don't talk about this, but they do talk about graphics DMA aborting when using holy DMA. It's conceivable that it could abort DMA when X is outside the range of the buffer. I suppose I could make a test to see what happens. Otherwise what I'll do is change the width to 1 to minimize graphics fetches (normal width is 3 bytes) and move off screen at the same time. I don't expect to have font space to spare.

I'm trying to figure out the most efficient way to erase a character when using static display list entries. Does it save Maria cycles to move an object off screen vs. changing it to a blank object? I'm wondering how Maria treats a DL entry that is off screen, outside the 160 pixel line buffer. My guess is that Maria would still use 8 cycles to read the 4 byte header, but it should not need to read the graphics bytes (3 cycles each) if the x position is outside the 160 pixel wide buffer. If I erase an object by changing it to a blank character, Maria would still need to read the graphics data for the blank character. I could be wrong though. Maybe Maria still reads the graphics bytes but does nothing with them because the x position is off screen.