Getting G3 Whisper Perch USB working

[croissantking]

Tonight I installed an 82C861 chip and oscillator on @Dandu 's personality card, which I'll be returning to him in France once complete. System Profiler lists both the USB card and a corresponding USB bus, which is the expected behaviour.

We were pretty confident the 82C861 chip would work, but now we know with more certainty.

 

[croissantking]

So here's a pretty big twist in the story.

The Opti Firelink 82C861 does NOT work on the personality card!

At least not with the current design.

I finished assembling @Dandu 's card and it would not recognise any USB devices that were plugged in, not even to throw up errors.
As a test I swapped over the chips on my own working card and his; it sprang to life with the CMD 0670B-400, and mine stopped working.

I am really suprised as the Opti chip is advertised as pin compatible with the CMD chip. I am still convinced it can be made to work with some modifications to the passives that we selected. I wonder if it is a voltage issue.

 

[Phipli]

So here's a pretty big twist in the story.

The Opti Firelink 82C861 does NOT work on the personality card!

At least not with the current design.

I finished assembling @Dandu 's card and it would not recognise any USB devices that were plugged in, not even to throw up errors.
As a test I swapped over the chips on my own working card and his; it sprang to life with the CMD 0670B-400, and mine stopped working.

I am really suprised as the Opti chip is advertised as pin compatible with the CMD chip. I am still convinced it can be made to work with some modifications to the passives that we selected. I wonder if it is a voltage issue.

Compare the datasheets. Boring, but needed, unless an ex designer that spent 10 years using both chips happens to walk past. Which is unlikely.

 

[croissantking]

I think I’ll put my efforts into sourcing a supply of CMD chips - one has to know when to draw the line, and I unfortunately don’t have the expertise or energy to solve this alone. It’s likely I’d damage my personality card if I fiddle about with it too much. We’ve achieved so much and I’d hate to destroy my creation.

Maybe this can be revisited at a later time if there’s enough interest.

What I am quite keen to do, now that I have a Yikes! board, is to beep out the startup circuit and draw a schematic. It’ll get us closer to understanding how to populate the one on the personality card

 

[croissantking]

To anyone interested in performing the mod to their Whisper card, here is a Mouser cart with all the parts needed (other than the IC):

https://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=ed20c4f711

I have also updated and tidied up the BOM on Github:

G3-Personality-Card-USB/G3 Personality Card USB BOM.csv at main · CroissantKing/G3-Personality-Card-USB

Contribute to CroissantKing/G3-Personality-Card-USB development by creating an account on GitHub.

github.com

Something I learned on this project is that an inductor and a ferrite bead are *not* the same thing

 

[just.in.time]

We’re you able to identify a supply of the CMD chips?

 

[croissantking]

We’re you able to identify a supply of the CMD chips?

I haven't, yet.

 

[just.in.time]

I picked up a new in box USB 1.1 card. The picture on the box had the correct CMD chip but when I opened the packaging the card had a different CMD chip (totally different numbers and square shape instead of rectangle).

 

[croissantking]

That's annoying. I did know that the CMD chip was available in two types of package because it's mentioned in the datasheet, but I've never seen the square one. Photo?

 

[just.in.time]

Will upload that this weekend.

 

[croissantking]

Will upload that this weekend.

Did you manage to photograph it? Would love to see it

 

[croissantking]

So I bought a card with the CMD chip onboard (see photo below - looks like the reference design we were looking at previously) and I placed a Firelink chip in its place. Works perfectly.

Whatever is preventing it from working on the personality card must be a very minor thing.

 

[Dandu]

I have a card modified by @croissantking and i have write a thing about the card (in french, i will try to make an english version soon) : https://www.journaldulapin.com/2023/08/04/power-mac-g3-usb/

I have tried with USB flash drive, a mouse and a keyboard, and it works like a charm with Mac OS 9 (i have not Mac OS X on my Beige G3)

 

[croissantking]

I have a card modified by @croissantking and i have write a thing about the card (in french, i will try to make an english version soon) : https://www.journaldulapin.com/2023/08/04/power-mac-g3-usb/

I have tried with USB flash drive, a mouse and a keyboard, and it works like a charm with Mac OS 9 (i have not Mac OS X on my Beige G3)

It’s interesting that your Apple System Profiler lists the card under just ‘Connecteur’ rather than ‘Connecteur PERCH’/‘Slot PERCH’ as mine does.

Your mod went really smoothly apart from the confusion when the Opti Firelink chip didn’t work! Dremeling out the backplate is quite difficult as Apple used thick sheet metal, but I’m getting better at it.

 

[Phipli]

Dremeling out the backplate is quite difficult as Apple used thick sheet metal, but I’m getting better at it.

I tend to chain drill and then use a file. It's easier not to slip and doesn't take much longer.

 

[joevt]

It’s interesting that your Apple System Profiler lists the card under just ‘Connecteur’ rather than ‘Connecteur PERCH’/‘Slot PERCH’ as mine does.

I think it would have said "Connecteur PERCH" but it was too long to fit so it wrapped? "Slot PERCH" is much shorter.

 

[croissantking]

I think it would have said "Connecteur PERCH" but it was too long to fit so it wrapped? "Slot PERCH" is much shorter.

I thought of that indeed, maybe that’s why.

 

[Dandu]

There is many weird things like that with Mac OS 9 in french

 

[StevieC]

does the "Bordeaux" personality-card (the one with a DVD-Video compatible MPEG2 decoder-chip onboard) also have the solder-pads and headers for a USB-port?

 

[croissantking]

does the "Bordeaux" personality-card (the one with a DVD-Video compatible MPEG2 decoder-chip onboard) also have the solder-pads and headers for a USB-port?

It does.