VBXE

[Tempest]

Hate to bump an old thread, but has anyone gotten a VBXE running in an Atari 800 with the Incognito?

[jasonbar]

Thanks for bumping.

 

Now that I've just finished tackling the RGB mod on my 3DO FZ-10, I'm feeling bold enough to do the RGB VBXE on my 130XE. If that goes well, I'd love to get a 2nd VBXE & do my 800, so I hope to hear some good news about this!

Thanks,

-Jason

[Tempest]

I'd settle for a cheaper RGB board without all the extra graphics modes, but that market would be even smaller than the current VBXE market.

[jasonbar]

Emboldened by successful installation of a Vectrex monitor cap kit, I finally cracked open my 130XE to see what was involved in installing the VBXE.

 

It's a bit daunting. It seems that my Antic chip is not socketed. Dang.

 

I'm also confused by the manual. My 130XE matches the 2nd one shown on p. 11 in the manual, which is labeled Atari 65/130XE, 1 Bit Memory Chips.

 

Mine was modded at the time of purchase waaaaaay back when with a switch to enable 192kb of RAM instead of 128kb, to allow for a full-size RAM disk. That's why you see extra memory chips & wires on my attached pic.

 

 

Frankly, I'm a bit lost on what to do. I gather that I need to desolder my Antic chip (C021697). Then, I solder in the VBXE where the Antic was, & I pop the Antic into the VBXE's socket.

 

Then, do I simply make 7 connections as shown on the table on p. 7 (also attached)?

 

Any help or hand-holding or guidance is much appreciated!

 

Thanks,

-Jason

[Rybags]

You solder in the precision socket where Antic is - that should be the first thing done, then put Antic back into it temporarily to test it.

The end installation, the adaptor board actually goes into that socket with Antic plugged on top.

 

Existing Ram upgrade should be OK with VBXE. But 192K is one of those middle of the road things where lots of stuff won't run because it wants 320K.

VBXE in this config should run the "A" core firmware - that doesn't present any VBXE Ram as expanded system RAM.

VBXE with the "R" core firmware presents 256K as a Rambo equivalent which makes the system appear to have 320K which is compatible with much existing software that requires it.

 

But with 192K Ram already, I don't think you'd be able to run the "R" core.

[jasonbar]

Thanks--so, there should be no other wiring beyond removing the Antic & then some socketing?

 

The manual describes some extra wiring required, shown in my previous post.

Thanks!

-Jason

[Rybags]

Should be no other wiring beside what's in the docs.

 

The trickiest parts are doing the Antic socket and desoldering the 14 MHz crystal - the solid type as pictured is harder to do than the other types.

[jasonbar]

Howdy-

 

Thanks for the reply again.

Progress last night! I managed to remove my Antic chip with relative ease. Wow! I cranked the Weller up to about 830F, applied heat to each solder pad until it flowed, then quickly sucked up the solder with my cheap plastic "clicker" (see attached for a pic of one that looks like mine). That did most of the work. Then I made a couple passes with a lower temperature & some copper braid to suck up the remainder of the solder. Then, very gentle prying popped it out. Only 1 hole needed a little cleaning.

 

The socket inserted nicely. Soldered it in. Popped in the Antic, fired 'er up, got the blue "READY" screen.

 

I didn't break anything! :]

 

Next up, pop in the adapter board, the Antic, etc. Will report back with progress. If I can't figure out the remainder of the process, at least I can go back to stock, with a socketed Antic.

 

Thanks,

-Jason

 

PS--I can't decipher p. 11 of the manual. My mobo crystal is like the one shown in the main picture, a DOC-20N 14187.57KHZ KDS-5B. It's not the little one shown in the "OPTION" view. The way I read it, I should keep my crystal on the mobo. Am I reading that wrong?

 

PPS--regarding memory & such, all I really want is to put out RGB video. I don't plan on running RAMdisks or doing anything fancy. :]

[jasonbar]

More slight progress last night (spent most of last night's free time making a new Vectrex joystick centering spring).

 

Popped out the Antic from the socket.

Inserted the adapter board into the socket. VBXE still set aside.

Popped the Antic into the socket on top of the Antic board.

 

Powered up. Still got the nice blue "READY" screen (using S-Video at the moment).

 

 

I realize now that I didn't get a SCART cable. Lotharek didn't offer it when I bought my VBXE.

Per p. 13 of his installation guide, it appears that I need to simply wire R, G, B, sync, GND, composite, & audio into a connector & then to the SCART connector.

 

A few quick questions on this:

 

1 - Many SCART/RGB cables seem to need resistors in line with some of the pins. Not so in this case?

2 - The SCART RGB cable needs Composite Video from the monitor jack. Looks as if that's pin 4 on the monitor jack. I think I've got that figured out--I'll look for teeny numbers on that connector & try to see which one is 4. (I often get confused on which direction/gender I'm viewing when looking at connector pinout diagrams.)

3 - I'm going add my own RGB connector jack at the rear of the 130XE. Will the existing monitor jack on the 130XE (for S-Video) remain operational after installing the VBXE & hooking up the RGB connector?

4 - When I installed 3DO RGB kits, I removed the RF output circuitry (which I'll never use again anyway) & used that space & opened up the existing hole. That looks like the plan on the 130XE also. Will RF removal booger anything up, or is it safe to remove?

Thanks,

-Jason

[flashjazzcat]

1 - Many SCART/RGB cables seem to need resistors in line with some of the pins. Not so in this case?

Not so in this case.

 

2 - The SCART RGB cable needs Composite Video from the monitor jack. Looks as if that's pin 4 on the monitor jack. I think I've got that figured out--I'll look for teeny numbers on that connector & try to see which one is 4. (I often get confused on which direction/gender I'm viewing when looking at connector pinout diagrams.)

It should be the second one along under the board, counting from the power jack end of the motherboard. You can also take Sync from CD4050 (as indicated in Candle's original instructions).

 

Note in the context of SCART, sync goes to composite sync (monitor jack or CD4050) while SCART's RGB select signal is sourced from the VBXE header.

 

3 - I'm going add my own RGB connector jack at the rear of the 130XE. Will the existing monitor jack on the 130XE (for S-Video) remain operational after installing the VBXE & hooking up the RGB connector?

Yes - the original video output will still work.

 

4 - When I installed 3DO RGB kits, I removed the RF output circuitry (which I'll never use again anyway) & used that space & opened up the existing hole. That looks like the plan on the 130XE also. Will RF removal booger anything up, or is it safe to remove?

Hmmm... isn't composite generated inside the RF mod in the XE? In which case, go for the CD4050 hook-up for sync. A slightly better option is a gated sync: take the 4050's sync and feed it back into one of the spare getes on the IC (tied to GND until you cut the trace). You can then take sync from that gate's output and it's pretty much compatible with anything.

Edited June 3, 2014 by flashjazzcat

[jasonbar]

A tad of progress this weekend.

 

1 - Ordered Neo Geo SCART cable: http://www.ebay.com/itm/161253121219 . I've used these guys' cables before on other RGB-modded consoles & they're good (had trouble w/ my NES-101 RGB mod, & switching to their shielded cable fixed the problem--after much fruitless troubleshooting...) & ordered a 6-pack of panel mount DIN 8 female connectors: http://www.ebay.com/itm/151127206607. The Neo Geo cable doesn't have resistors etc. in it, so it seems to be a good fit for the VBXE in my 130XE.

 

2 - Thanks--yes, I should be able to pull "composite" from the monitor jack.

 

4 - I removed the RF modulator guts (shield box + PCB + rear jack). This will provide plenty of room for the new DIN 8 jack. A quick test showed that the S-video & audio still work fine on the stock monitor jack. Another quick check shows that simply plugging in the VBXE board into the socket w/ the Antic makes the computer not work. I think that's where the crystal move comes in--I'll have to study that some more.

 

Thanks,

-Jason

[Rybags]

You don't really want to have the VBXE partially installed in that way.

The initial vital test is that the system still works with only the Antic removed and socket installed, and with Antic installed on the adaptor board.

 

The install after that is pretty simple, and the critical part then becomes using the VBXE as the master clock provider.

[jasonbar]

A little more progress:

 

1 - I got a SCART cable & panel-mount connector. Many use resistors & capacitors inside the cables, but the VBXE needs a "straight" cable. So, I sought an equivalent cable with a connector that was not only big enough to handle & connect easily, but also one where I could find a nice panel-mount connector. I ended up with Neo Geo & DIN 8:

http://members.optusnet.com.au/eviltim/gamescart/gamescart.htm#neogeo

http://cgi.ebay.com/ws/161253121219

http://www.ebay.com/itm/151127206607

 

 

2 - I pulled the clock crystal off the 130XE motherboard. Pretty easy.

 

3 - I wired up the VBXE to the motherboard as shown.

 

4 - I soldered flying leads to the VBXE's output pads.

 

5 - My baby boy woke up from his nap before I could fit the DIN 8 to the case.

 

 

One quick question during fitup. The VBXE interferes with the cartridge ports on the rear of the 130XE. I can't seat it down fully on its header from the little adapter board. I've sketched the VBXE outline on the attached photo for illustration. Do I need to nibble away at the gray computer case? If so, I think I'll nibble through to the outside.

Thanks,

-Jason

[flashjazzcat]

I think you may have the adapter on backwards. The VBXE should overhang GTIA, not the CPU.

[jasonbar]

Thanks. In the installation manual, there are few photos showing the VBXE installed, & they all appear to point the PCB backwards.

 

See picture 1. Pin #1 notches are on left side in both photos. The VBXE board is pointing "up" relative to the left pin #1 notches.

 

And, on picture 2, showing the whole PCB, the notches are also all on the left. Therefore, it seems that the VBXE PCB should point "up" toward the back of the 130XE.

 

 

Thanks for the feedback. So, if I turn the adapter board around 180 degrees to hang the VBXE over the GTIA (front of case), then the Pin #1 notch on the adapter board won't be aligned with the Antic Pin #1?

Thanks,

-Jason

[flashjazzcat]

I don't understand the perceived correlation between the IC notches being on the left and the VBXE overhanging the CPU. The adapter is the right way round. The VBXE is plugged into the adapter backwards.

[jasonbar]

Thanks. If I had a picture of the VBXE installed into a 130XE, not at such a close-up distance, it would clear up a lot of confusion.

 

I'll install in the items as I think they're to be oriented & share some pictures here for confirmation before powering it up.

 

-Jason

[flashjazzcat]

Google image search: "VBXE 130XE".

[lotharek]

in manual - LEFT COLUMN XE series, RIGHT _ XL !!

Edited July 5, 2014 by lotharek

[atari8warez]

Hate to bump an old thread, but has anyone gotten a VBXE running in an Atari 800 with the Incognito?

 

What's wrong with bumping an old thread so long as the new conversation is still related to the original subject. I am asking this seriously as there may be a fine point that I am missing as I am not a forum moderator.

[jasonbar]

Thanks for your continued support! A little more progress. I'm getting close--I can almost taste the RGB!

 

Finished wiring up everything on the VBXE & the Neo Geo DIN 8 SCART cable, installed the connector where the RF hole was.

 

 

Tested the 130XE 2 ways: SCART via new DIN 8 connector, & S-video/stereo via stock monitor connector. Nothing. Blank. Get red power LEDs on 130XE & VBXE. No "flatulence" sound on power-up.

 

 

I inspected the installation. Wiring seems to be in order. The mate between the adapter board's 40 underside pins & the socketed I soldered to the motherboard was a little crooked, which happened when I pushed down on the VBXE's header connection to secure it to the adapter board. I straightened things out and......partial success!

 

 

 

Here's where it stands. I seem to have a sync problem.

 

- RGB shows what appears to be the blue "READY" screen, but out of sync. I'm using a Sony PVM & switching to "SYNC ON GREEN" didn't fix it. Hmm, also no sound, but I'm not worried about debugging that later. My monitor can accept PAL input--I've done that before. I also confirmed that the VBXE jumper is on NTSC, not PAL.

 

- S-video stock monitor cable produces sound, & I did get the "READY" screen as expected, but it was in black & white (well, gray & white). I probed around, checked connections, things seem to be in order, powered again, but now the S-Video is putting out out-of-sync dark blue video (and audio is still good).

 

 

I've mucked a bit with the pot accessible through the bottom of the 130XE, & it seems to do nothing when using RGB but can replace the dark blue squiggles screen with a blank screen if I crank it all the way to one side.

 

 

Any troubleshooting advice before I ring out everything? :]

Thanks!

-Jason

 

PS--tested my RGB 3DO right after these tests--confirmed monitor & SCART/audio extension cable are good. :]

[Rybags]

Sync is composite sync which is sourced from the motherboard. I had the same problem first up, had forgotten to put in that connection. If the monitor has some selection ability, it'd need to be seperate composite sync, VBXE doesn't use Sync on Green, or seperate H/V Sync.

In some cases where only seperate syncs are provided, the usual is to tie the CSync output to HSync on the monitor.

 

If you're getting sync problems with normal video as well then that'd indicate a problem somewhere else.

 

Colour adjustment Pot will make absolutely no difference to RGB, VBXE video is independant except for the shared CSync.

 

Sound - I guess you source that from the normal monitor port? In any case, I'd be getting the video output right before worrying about sound.

Edited July 6, 2014 by Rybags

[lotharek]

SYNC is missing. Your monitor beahaviour is like mine sony pvm. i had to change in monitor setting sync to external one. besides it accepts csync pure signal and composite video as synchro input. rgb wiring is ok. i would also chceck gnd.

[jasonbar]

Thanks again for the input. I went through all of my wiring. All seems to be intact & correct. Image behavior remains the same.

 

When ringing it all out, I did notice that Lum, pin 1 on the stock monitor connector, has only 145 ohm to ground. Normal? I don't seem to have perturbed that part of the circuit.

 

 

Also, when using RGB, I *do* have sound, but it is veeeeerrrrry quiet--I have to crank my speaker bar to the absolute maximum volume, & then I can just baaaaarely hear the flatulent startup sound.

 

I tried cutting my Audio & Composite Sync connections that feed the RGB connector from the stock monitor connector. No change.

 

Most of the VBXE installations that I saw in another thread here ( http://atariage.com/forums/topic/152939-show-your-vbxe-installs/ ) have the RF modulator circuit intact. Some have it removed. I removed mine. Should it be replaced? I wasn't super careful with its removal--it might be impossible to replace it... :\

 

Any ideas? :\

 

 

---

 

I've also found that the adapter board & VBXE are very very very sensitive to misalignment. Just a little nudge on either seems to remove contact somewhere & the machine reverts back to the "no flatulence" startup routine.

 

 

Thanks,

-Jason

[jasonbar]

PS--per an above post of mine, s-video was still working after removing RF.