I also have this TOS switcher: I installed this a few days ago. TOS boots no problem against the native CPU.
For the booster:
- I've soldered the single-core wire between the soldering point on the booster and the appropriate pin on the 74F257. Pleasant surprise: my board had a 74F257 in place already.
- I've soldered the top-right soldering point on the booster to the "CE" soldering point on the dual-TOS board. I used the cut-off from the single-core wire here too; I wasn't sure how sensitive that connection needed to be.
- I've wedged the booster into place in the socket using the dummy CPU.
But, my problem: the first thing I wanted to do was to run gembench from my sidecart or from my older tester cartridge. Neither cartridge works with the booster in place while boosted.
If I pull out the booster out and stick the old CPU in: the sidecart works a-okay. If I put 0v on the appropriate soldering point to put the booster into 8MHz mode, the cartridge port also works. Otherwise, with the booster at 32MHz, the sidecart gets power (an LED blinks on power-up) but the STE doesn't read it.
The machine is generally stable, with a recapped CPU, a recent 4MB upgrade, and one of the axial cap kits from the store installed a few months back, too.
I wonder about this mandatory fix and I can't recall if I replaced the resistor packs on this board a few years ago. On a very quick check, looking at the resistor packs that are exposed:
P100 is 1.2k, which is what the instructions say is necessary for the booster
P104 and P105 seem to read at around 3.1k.
That's all I know, so far; mainly I'm wondering if there's something likely that I ought to look at here. Maybe the resistor packs are the culprit. I'll get time to debug properly soon.
