faulty AtariVox(es)

[bomberpunk]

my unit does all the fancy speech synth but fails to record data to it. i discovered this while playing Strat-o-gems and confirmed it by trying Fall Down as well as the flawless SaveKey.

 

refer to this thread and start with post #274 at the bottom.http://www.atariage.com/forums/index.php?s...8579&st=275

the discussion (and an explanation) continues on page 12.

 

are any of you new owners experiencing the same results?

 

for the record (i'm not sure if it would matter) i have the vader version of the 2600.

Edited January 19, 2007 by bomberpunk

[Richard H.]

You have a bad EEPROM in your AVox.

 

The circuitry for the memory save in the SaveKey and AVox are identical.

 

The 10K pull-ups were added to the new version of the AVox (and SaveKey) as the old one (un-cased) did occasionally glitch on 2 games (MGD and Strato).

(I posted instructions for fitting these resistors to the old model)

 

John (Supercat), asked me (and Albert) to test the new units with his game just to be 100% sure it worked OK, which it did.

 

Get in touch with Albert for another, or if you're handy with the soldering iron, I can send you a replacement EEPROM.

[Richard H.]

Albert's very busy right now, so just send it to me and I will repair it for you.

[Thomas Jentzsch]

...as the old one (un-cased) did occasionally glitch on 2 games (MGD and Strato).

Do you know why only those games glitched? Anything special with their code?

[bomberpunk]

Albert's very busy right now, so just send it to me and I will repair it for you.

 

PM sent

[Richard H.]

Do you know why only those games glitched? Anything special with their code?

Don't know.

 

I do know that since the pull-ups were introduced it cured the problems.

[+Nathan Strum]

My only complaint about the AtariVox (in the new case) is that it doesn't fit snugly into a six-switch joystick port. The 2600's ports are slightly recessed, and the plastic tabs that hold the 9-pin connector in place on the AtariVox prevent it from being inserted all the way.

 

It goes in far enough to make contact, and seems to stay in place okay, but it's not a very good fit. I may end up getting a 9-pin "y" cable for it.

 

I'm also thinking about getting one of these, so I can hook it up with the output of my A/V mod. (Either that, or building a simple circuit.)

[supercat]

Do you know why only those games glitched? Anything special with their code?

 

The RIOT chip has relatively weak pull-up circuitry on the joystick ports. When the Atari tries to output a "high" signal to one of the EEPROM pins, the signal will go high with or without a pull-up, but it will go high must faster with. Strat-O-Gems inputs and outputs data pretty fast. Without pullups, the EEPROM pins won't react as fast as the code is trying to drive them. The problem could be fixed either by adding resistors, or by having the code run slower; the latter option would not work well for Strat-O-Gems, however, because of the need to write a fair chunk of data during vertical blank and overscan without disrupting game play.

[Richard H.]

the plastic tabs that hold the 9-pin connector in place on the AtariVox prevent it from being inserted all the way.

Just cut the tabs flush with the case.

 

(the tabs aren't really needed, the PCB is secured as it's the same outline shape as the case)

 

BTW has the metal surround been removed on your connector ? -

Edited January 21, 2007 by Richard H.

[+Nathan Strum]

Just cut the tabs flush with the case.

 

(the tabs aren't really needed, the PCB is secured as it's the same outline shape as the case)

Can do. Thanks!

 

BTW has the metal surround been removed on your connector ?

Nope. Was it supposed to have been?

[Richard H.]

Nope. Was it supposed to have been?

Doesn't really matter, but it would have given you a little more connector length.

 

Go with the tabs removal

[Thomas Jentzsch]

Strat-O-Gems inputs and outputs data pretty fast.

With fast you mean all the reads and writes for storing a new highscore at once, right?

 

the latter option would not work well for Strat-O-Gems, however, because of the need to write a fair chunk of data during vertical blank and overscan without disrupting game play.

So you would have to make a pause between each I2C access, right too?

 

I wonder how the other, unaffected games write their data. I suppose all games are using the same i2c.inc file, so there must be a huge difference somewhere else.

[Richard H.]

I'm not a coder, but it sounds like now the pull-ups are in, the driver could be made to go much faster.