(Topic ID: 122931)

Clearing memory from Two Bits -35 with fix it rom?

By Lovef2k

9 years ago

Topic Stats

5 posts
2 Pinsiders participating
Latest reply 9 years ago by Lovef2k
No one calls this topic a favorite

You

You are not signed in!

Find in topic

Linked Games

Seawitch Stern Electronics, 1980

Not sure if this applies but I have junk in my Seawitch displays using my twobits -35. I bought it new from them about 7 years ago. It hasn't been used a whole lot and every game I try it in will usually work. In this case the game boots and goes into attract. Also goes into test mode, but not always. I cleared out all the audits, high scores etc. using switch 33 on the mpu. Game will not start or coin up. The dips are set to Seawitch as per two bits chart.

I search their webits but didn't find anything for memory clearing. Alltek MPU's have a clearing option, I thought maybe twobits does as well.

just clear all the audits with the coin door buttons. It can be done in 30 seconds. Get to the audits. Hit the cycle button, clear, cycle button clear, etc to the end.

There is no memory check for scrambled ram in these games like WMS did. If the CPU runs wild and drops a load on the RAM or the batteries die, you will end up with random junk in the RAM. Clear it manually and you are good to go. Most of the audits are worthless to a home use game. Just clear the first 6 or so, those are the high score ones typically.

Andrew

Quoted from barakandl:
just clear all the audits with the coin door buttons. It can be done in 30 seconds. Get to the audits. Hit the cycle button, clear, cycle button clear, etc to the end.
There is no memory check for scrambled ram in these games like WMS did. If the CPU runs wild and drops a load on the RAM or the batteries die, you will end up with random junk in the RAM. Clear it manually and you are good to go. Most of the audits are worthless to a home use game. Just clear the first 6 or so, those are the high score ones typically.
Andrew

Andrew. I did clear all the audits, high scores etc, one by one as you described. I also replaced the fixit rom with a newer one since there is a lithium battery on the fixit rom. Still junk, but different junk!

In the mean time I had an mpu 200 laying around and didn't know if it worked. The SW came with an alltek mpu and the game ran fine. I needed it for another game which I sold together. I bought new eproms (2732) and jumpered the mpu for them. Also replaced the 5101's and the 6810 ram. There's no battery on this board. Amazingly the mpu booted and them game went to attract. Still getting the junk. The displays show numbers with spaces between them. 4 digits lit and 3 blank. I went into self test and the game shut down. restarted again ok.

So basically the same result with 3 mpu's. Problem must be the game. I'm thinking coin door. Everything else works, coils, sound feature lamps etc. Also no stuck switches.

OP
Quoted from Lovef2k:
Andrew. I did clear all the audits, high scores etc, one by one as you described. I also replaced the fixit rom with a newer one since there is a lithium battery on the fixit rom. Still junk, but different junk!
In the mean time I had an mpu 200 laying around and didn't know if it worked. The SW came with an alltek mpu and the game ran fine. I needed it for another game which I sold together. I bought new eproms (2732) and jumpered the mpu for them. Also replaced the 5101's and the 6810 ram. There's no battery on this board. Amazingly the mpu booted and them game went to attract. Still getting the junk. The displays show numbers with spaces between them. 4 digits lit and 3 blank. I went into self test and the game shut down. restarted again ok.
So basically the same result with 3 mpu's. Problem must be the game. I'm thinking coin door. Everything else works, coils, sound feature lamps etc. Also no stuck switches.

If you have no battery on the board, the RAM gets scrambled every time you power off. High scores with missing digits (hex code about 9), etc

The software crashes if you hit the clear button before hitting the enter audit button. Make sure you dont press the clear button before hitting the audit button.

If the software still crashes when you try to get into audits then there is a problem with the coin door button/wiring. Map it out with the manual. Look for shorts against the coin door.

Andrew

Will look at the coin door this weekend, thanks!

Promoted items from Pinside Marketplace and Pinside Shops!

Reply

Wanna join the discussion? Please sign in to reply to this topic.

Hey there! Welcome to Pinside!

Donate to Pinside

Great to see you're enjoying Pinside! Did you know Pinside is able to run without any 3rd-party banners or ads, thanks to the support from our visitors? Please consider a donation to Pinside and get anext to your username to show for it! Or better yet, subscribe to Pinside+!

Help – Contact – About Pinside – Support Pinside – Top