Successful 1.5 booster install in STM c070243 rev H

[Steve]

I just finished installing the 1.5 booster in my STM. There weren't any instructions for installing it in my machine as it has no CE section on the motherboard like STFM's have. So exxos kindly gave me the following information:

"You need 3 diodes 1N4148...
Solder the "white line end" of the diode to CE (pin 20) of the 3 HI ROM's. (one diode per HI ROM)
Then the other 3 ends of the diodes, solder them all together, then that is your CE line for the booster."

There was also a 5v pullup resistor which I soldered to a diode leg near the CPU to provide 5v. I don't know the resistor value maybe Chris remembers.

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^ Here I wanted to install the diodes as neatly and cleanly as possible, so I opted for the rear of the motherboard rather than solder directly to the TOS pins, just in case I might swap my TOS roms one day (with all the talk of Peter Putniks improved roms etc)

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^ Here I managed to solder them together neatly and ran the cable through a handy hole in the PCB to the top side.

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^ I neatly routed the cable through the TOS roms, through a diode leg and then up underneath the CPU through it's legs and onto the CE port.

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^ Here I connected the booster from the CE port to 5v off a diode leg with the resistor

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^ Just a shot of the overall machine

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^ Gembench results vs a stock STM.

Overall I am really happy with the results, I also managed to re-cap the machine since I had it apart. I have a bad habit of doing too many things at once, so if I have issues I don't know what caused them But luckily everything was good. This must be the ultimate STM now, running at 16mhz and 4mb of ST RAM

Thanks for all the help Chris

Kind regards,

Steve

[exxos]

Thanks for posting this, will be helpful for others I'm sure!

[PaulJ]

Nice job!

[IngoQ]

Looks very neat, congrats And I just love the union jack on it

[nemox]

Hi.
Pls value of The 5v pullup resistor?
thanks

[exxos]

Pls value of The 5v pullup resistor?

Not really important, any value like 1K, 4K7, 10K, 22K will be fine.