exxos's Atari, Amiga & retro forum

I see lots about the hardware install. Is this purely a hardware device? nothing done in software?

So the line to ground that controls 8/16mhz switching... do I put a switch on it if I want to go back and forth? I dont see anything in the hardware page that says that grounded is 16mhz open is 8mhz.. or that there is software switching.. so I assume I need a switch?

Thanks
James

Bikerbob wrote: 05 Mar 2025 00:13 I see lots about the hardware install. Is this purely a hardware device? nothing done in software?

So the line to ground that controls 8/16mhz switching... do I put a switch on it if I want to go back and forth? I dont see anything in the hardware page that says that grounded is 16mhz open is 8mhz.. or that there is software switching.. so I assume I need a switch?

Thanks
James

Yes, just put a switch inline to switch speeds. The STE 32Mhz boosters I have are the same and IIRC grounded is the faster speed, but you can work it out by testing with Gembench to see what position is faster.

It's not like the MSTE where it was software controlled.

with this booster, anything that reports mhz of the machine, should see the 16mhz now?

Or will it still report as 8mhz even though its now faster?

Hmmm.. maybe i need to trouble shoot.

James

sysinfo will sometimes report 12MHz in some cases, or more likely 8Mhz. If I remember rightly, GND the select cable forces 8MHz.

You just need to run GB6.. you will get this if your in 16MHz mode..

SO it would seem I cant get switching to work.

I am only running at 8mhz no matter what I try.

Checked it wired up 4-5 times now.

ITs on a H5c1 board.

James

I assume you have actually connected the 16 megahertz wire to the shifter ? And using a HC CPU in the booster and removing the motherboard CPU ?

Install page is here https://exxosforum.co.uk/atari/last/V22 ... /index.htm

I think you struggle installing on a H5 as where are you soldering the BG wire to ? The 2.2 was only designed for the 70789 type boards. There's no other install steps other than the mega which I don't even bother with now.Things have moved on a lot since then. V2.2 is a decade old now...

Yes I did.. I have included 3 pictures.

I connected the BG to pin 11 of the cpu slot - see picture. Your install guide said via of pin 11 so I assumed pin 11 was good.. the H5 gives ample opportunity to wire it up.

So maybe it wont work at 16mhz on the H5.. Im just trying.. finding something to do with the board. This is not make or break. Just trying to figure out why its not working. OTHERWISE - yes.. cpu in booster.. everything else is working fine.. just no speed switching.

James

Scope the CPU clock see what's there...

Do you have 5v on the speed select wire ? I think they may be a omission in the docs.. But I can't remember after 10 years how it was built.. But 16MHz needs 5V to enable. Which means either your do this via the switch, or add something like a 1K pullup resistor on the GAL SW pin to 5V there. That resistor if added, would likely be on the bottom of the PCB as a normal resistor bodged on..

exxos wrote: 07 Mar 2025 04:42 Scope the CPU clock see what's there...

Do you have 5v on the speed select wire ? I think they may be a omission in the docs.. But I can't remember after 10 years how it was built.. But 16MHz needs 5V to enable. Which means either your do this via the switch, or add something like a 1K pullup resistor on the GAL SW pin to 5V there. That resistor if added, would likely be on the bottom of the PCB as a normal resistor bodged on..

So your saying I should have 5v at pin 13 of the GAL? I can check that.. there is at least one resistor bodged on the back. I will take a pic of the back of the booter, it seems to go between 2 pins on the LH side GAL. I will post the picture.

James

Bikerbob wrote: 07 Mar 2025 16:10 So your saying I should have 5v at pin 13 of the GAL?

Yes.

Pin1 should have 16MHz on it..