Jump to content
Curt Vendel

Happy New Year... XM shipping this month

Recommended Posts

Thanks Mike. I got in some 2222s and some variable resistors and some breadboards.

Spending tomorrow on the bench working the problem. Also Mark sent me a BIOS update to try out.

Just got tied up with work and things for the house. But tomorrow I have an open day finally to work on the XM

Did this latest round of testing yeild any positive results ot bring you any closer to resolving the issues with the Pokey and Yamaha adudio output levels? Just thought I'd check. Not rushing you nor demanding an update. Just curious how progress is going.
  • Like 1

Share this post


Link to post
Share on other sites

Did this latest round of testing yeild any positive results ot bring you any closer to resolving the issues with the Pokey and Yamaha adudio output levels? Just thought I'd check. Not rushing you nor demanding an update. Just curious how progress is going.

 

I would be fine ditching the Yamaha chip from the XM if it's continuing to be such a problem keeping the XM from reaching completion. It's not like there is any games that are ready to use it. The only one I know of was the possible Dig Dug with Yamaha audio and it's been publicly confirmed not to have been coded. I'd be more than happy with the XM reaching my front door without a Yamaha chip. You can't miss what you never had.

  • Like 4

Share this post


Link to post
Share on other sites

Hmmm...? Isn't that what Atari did with the "Amy Chip" for the ST...? They had problems getting it to work so the ditch the whole thing all together and ST users were stuck with the mediocre YM-2149? A slightly better chip than the Pokey, but still no where near as good as what the AMY chip had to offer. Sounds a little bit like a repeat of history if you cancel the YM 2151. Just saying that's all, but I can certainly understand the impatience for a final release of the XM module.

  • Like 1

Share this post


Link to post
Share on other sites

Thanks guys,

 

I've got some trimmer pots coming in and some fresh breadboards, I've cleaned off the entire audio section and I'm going directly from the 3 test points I have and I've wired 3 lines from it along with Analog GND and +5v that'll go to the breadboard and I'm going to spend some time working this through. I agree with Perry.... instead of running both Ch1 & Ch2, what I found was the volume increased substantially from the DAC when I combined the two lines. I went down as low a 4.7k on the resistor and while volume was improved, the gain and distortion was too high.

 

Sounds like some audio clipping with in the decibel; too much loud audio for the speaker to pick-up... I like how the Sega CD module had a mixing audio jack in the back of it to cover stereo sound exclusively from the module. It's possible to do the same on the XM using some cheap method to compensate to whatever changes will be made to the hardware.

Share this post


Link to post
Share on other sites

Hmmm...? Isn't that what Atari did with the "Amy Chip" for the ST...? They had problems getting it to work so the ditch the whole thing all together and ST users were stuck with the mediocre YM-2149? A slightly better chip than the Pokey, but still no where near as good as what the AMY chip had to offer. Sounds a little bit like a repeat of history if you cancel the YM 2151. Just saying that's all, but I can certainly understand the impatience for a final release of the XM module.

 

Getting the ST out the door meant an aggressive-and-accelerated development window. Shiraz couldn't get the AMY working in the ST so Atari Corp went to Sight+Sound for assistance. That meant ditching the AMY from the initial ST and why it was then planned for the 65XEM. Atari Corp would've probably included it later on in future ST models had S+S supposedly not double-crossed them. Atari Corp tried to get the YM2151 as a replacement for the AMY in the ST but Yamaha would only sell them the YM2149 because they were saving the YM2151 for their own music computer that they hoped would outsell the ST [the ST still demolished it outside of Japan amongst musicians].

  • Like 1

Share this post


Link to post
Share on other sites

Hi Everyone,

 

Okay... sorry about the Hiatus. I was focusing on exhibiting at VCF East and that took up a major about of my spare time as I did a fairly extensive exhibit on the 40th Anniversary of the Atari 400/800 computers there and Joe Decuir was very gracious to join me and come out to the show and the VCF team even setup a speaker spot for him on Sunday which was jam packed and it was a great talk.

 

So with that, I'm basic in "MARIA MODE" and I will be finishing up some final tweaking and testing of the audio amp, testing out the latest XM BIOS and posting some reports this coming weekend. Thank you everyone, now back to our regular programming....

 

 

  • Like 15

Share this post


Link to post
Share on other sites

Hi Everyone,

 

Okay... sorry about the Hiatus. I was focusing on exhibiting at VCF East and that took up a major about of my spare time as I did a fairly extensive exhibit on the 40th Anniversary of the Atari 400/800 computers there and Joe Decuir was very gracious to join me and come out to the show and the VCF team even setup a speaker spot for him on Sunday which was jam packed and it was a great talk.

 

So with that, I'm basic in "MARIA MODE" and I will be finishing up some final tweaking and testing of the audio amp, testing out the latest XM BIOS and posting some reports this coming weekend. Thank you everyone, now back to our regular programming....

 

 

 

So how about posting those results from 3 weeks ago please? Any closer to this thing finally being done? I really hope so!

Share this post


Link to post
Share on other sites

Hi Shawn,

 

You're right...

 

So here is audio test #1 of 2 (possibly 3) for today...

 

This is just the Yamaha 2151 connected up and running through a separate audio amp daughterboard circuit (huge thanks to Michael St Pierre for this suggested circuit.) I just changed out his 22K and 100k resistors and replaced them with variable resistors so I fine adjust the resistance and get things to the best result possible without having to constantly swap out resistors. Will update on final spec's once finished.

 

So this is video #1, this is ONLY the Yamaha circuit running through this daughterboard amp and then through the JP3 test point on the XM which feeds in to the Ext Audio line on the cartridge connector and brings the audio into the 7800 system.

 

IMG_8098.MOV

  • Like 6

Share this post


Link to post
Share on other sites

Hi Shawn,

 

You're right...

 

So here is audio test #1 of 2 (possibly 3) for today...

 

This is just the Yamaha 2151 connected up and running through a separate audio amp daughterboard circuit (huge thanks to Michael St Pierre for this suggested circuit.) I just changed out his 22K and 100k resistors and replaced them with variable resistors so I fine adjust the resistance and get things to the best result possible without having to constantly swap out resistors. Will update on final spec's once finished.

 

So this is video #1, this is ONLY the Yamaha circuit running through this daughterboard amp and then through the JP3 test point on the XM which feeds in to the Ext Audio line on the cartridge connector and brings the audio into the 7800 system.

 

attachicon.gifIMG_8098.MOV

 

With all that said, where does this place the current state of the XM please? Also, really nice to see a fully populated board in the mix even if the pokey isn't in tandem yet. I'm personally still of the mindset that if the Yamaha is really this much of a burden to the success and release of the XM it could be removed and most all users will still be very happy with the final product.

Share this post


Link to post
Share on other sites

 

With all that said, where does this place the current state of the XM please? Also, really nice to see a fully populated board in the mix even if the pokey isn't in tandem yet. I'm personally still of the mindset that if the Yamaha is really this much of a burden to the success and release of the XM it could be removed and most all users will still be very happy with the final product.

Basically:

 

1. Completion of full audio circuit.

2. Test of PIA installation, just for electrically connections and to ensure it is routed correctly.

3. 7800 versions final pass compatibility tests.

 

Once to this stage, then:

 

4. complete final board layout with all cut & strap changes.

5. Run final through hole board, populate and check all modifications and changes are correct.

 

At this stage:

 

6. Replace most components (with exception of legacy Atari IC's, and BIOS socket/IC with SMD/SMT parts.

7. Run final board layout check with new parts, hand solder components.

 

If all checks:

 

8. Send BOM and Gerbers to PCB factory for board runs. In house, the only things that'll need soldering at the SIO ports, DB15, BIOS socket and a few odds and ends keeping assembly to minimum. The PLD will be surface mounted to reduce assembly and errors, just needs to be JTAG'd and verified which is a 3 min process at most.

 

9. Start assembling into cases and packed them up.

 

10. Ship.

  • Like 9

Share this post


Link to post
Share on other sites

OKay - final revision.... I combined both Yamaha 3012 outputs together and fed them into the AMP circuit, the variable resistor is set at 6k (original design with 22K) and added the 2nd POKEY from an external cartridge into the design with a 100K resistor onto the summation line and all 3 audio devices are not all working together, no distortion or audio issues, the combined 3012 outputs actually improved the volume on the Yahama 2151.

 

So for your listening pleasure...

 

Michael St. Pierre... a HUGE shout out and THANK YOU!!!!!!!!!!!!!!! Your design was the basis for my final circuit, just tweaked it and changed a few things, but essentially used your basic premise and it worked like a charm, THANK YOU!!!

 

 

xm_audio_final_design.MOV

  • Like 18

Share this post


Link to post
Share on other sites

I guess this means you can cross off number one on your list now. :thumbsup:

 

Mitch

  • Like 3

Share this post


Link to post
Share on other sites

It appears that this conversation has been going on for a while now. Did these units actually ship in 2018?

Since the work is still ongoing.... that would be a no.

  • Like 1

Share this post


Link to post
Share on other sites

Does this order still exist?

 

Dear Matt Teske,
Legacy Engineering Store
Order Number: 2009969
Date Ordered: Wednesday 13 October, 2010
The comments for your order are: Update customer - email sent with order info. Order # 2009969
Your order has been updated to the following status:
New status: Update
Please reply to this email if you have any questions.

 

Copyright © 2011 Zen Cart. Powered by Zen Cart
This email address was given to us by you or by one of our customers. If you feel that you have received this email in error, please send an email to online.sales@legacyengineer.com

Share this post


Link to post
Share on other sites

 

Does this order still exist?

 

Dear Matt Teske,
Legacy Engineering Store
Order Number: 2009969
Date Ordered: Wednesday 13 October, 2010
The comments for your order are: Update customer - email sent with order info. Order # 2009969

Your order has been updated to the following status:
New status: Update
Please reply to this email if you have any questions.

 

Copyright © 2011 Zen Cart. Powered by Zen Cart
This email address was given to us by you or by one of our customers. If you feel that you have received this email in error, please send an email to online.sales@legacyengineer.com

 

Please make sure you've gone to 7800XM.com and gotten that submitted into the system so I will have your order info ready when these are good to go. Please be certain to include current shipping info please, thanks.

Share this post


Link to post
Share on other sites

Please make sure you've gone to 7800XM.com and gotten that submitted into the system so I will have your order info ready when these are good to go. Please be certain to include current shipping info please, thanks.

Just completed the form. No address change.

Share this post


Link to post
Share on other sites

OKay - final revision.... I combined both Yamaha 3012 outputs together and fed them into the AMP circuit, the variable resistor is set at 6k (original design with 22K) and added the 2nd POKEY from an external cartridge into the design with a 100K resistor onto the summation line and all 3 audio devices are not all working together, no distortion or audio issues, the combined 3012 outputs actually improved the volume on the Yahama 2151.

 

So for your listening pleasure...

 

Michael St. Pierre... a HUGE shout out and THANK YOU!!!!!!!!!!!!!!! Your design was the basis for my final circuit, just tweaked it and changed a few things, but essentially used your basic premise and it worked like a charm, THANK YOU!!!

 

 

 

attachicon.gifxm_audio_final_design.MOV

I think you meant to say "now" all these devices are working together and mistyped "not" when you stated "all 3 audio devices are not all working together".

  • Like 1

Share this post


Link to post
Share on other sites

I think you meant to say "now" all these devices are working together and mistyped "not" when you stated "all 3 audio devices are not all working together".

You sir, would be 100% correct..... all three are NOW working is definitely what I meant :-)

  • Like 12

Share this post


Link to post
Share on other sites

 

Getting the ST out the door meant an aggressive-and-accelerated development window. Shiraz couldn't get the AMY working in the ST so Atari Corp went to Sight+Sound for assistance. That meant ditching the AMY from the initial ST and why it was then planned for the 65XEM. Atari Corp would've probably included it later on in future ST models had S+S supposedly not double-crossed them. Atari Corp tried to get the YM2151 as a replacement for the AMY in the ST but Yamaha would only sell them the YM2149 because they were saving the YM2151 for their own music computer that they hoped would outsell the ST [the ST still demolished it outside of Japan amongst musicians].

 

Yea true that... The ST is still being used today in some studios. Would've been great though if it had that synth chip in it considering it was supposedly a better synth chip than the YM2151. The AMY was inspired by the work of "Bell Laboratories" work in music synthesis, which had a broader range of synth attributes to simulate real instruments. Certain would've only added to what the ST was offering.

 

Now back to the topic. lol :D

  • Like 1

Share this post


Link to post
Share on other sites

It's been another couple weeks since the last update. This thing any closer to my doorstep yet? :grin:

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...