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Re: non-socketed CPU
Posted: Mon Aug 28, 2017 1:12 pm
by IngoQ
exxos wrote: ↑Mon Aug 28, 2017 12:57 pm
Point being, your overall idea was to fit the booster ? The socket solution would be better *if* I had a plug in booster, which I do not. So this rules out the socket ideas totally as there is nothing to plug into it.
Okay, let's say I desolder my CPU and fit a PLCC socket instead on the mainboard.
Your current STE booster looks like this from the down side:
If I would now take your funky PLCC adaptor:
And instead of putting a PLCC
socket on it, i would put this PLCC
plug on it:
- PGA to PLCC Plug.gif (123.29 KiB) Viewed 8027 times
So this basically gives me a PLCC plug with "funky" layout, which I could solder on the downside of your current STE booster, right?
And afterwards I would have a pluggable booster, which could be removed and the original CPU could be placed in the socket on the STEs mainboard.
Or do I overlook something (again) ?
Re: non-socketed CPU
Posted: Mon Aug 28, 2017 1:23 pm
by exxos
Sounds like a plan
Though I do think that is making things more complicated than it needs to be though ?
Re: non-socketed CPU
Posted: Mon Aug 28, 2017 4:26 pm
by IngoQ
How so, besides buying a different board?
Re: non-socketed CPU
Posted: Mon Aug 28, 2017 4:40 pm
by exxos
IngoQ wrote: ↑Mon Aug 28, 2017 4:26 pm
How so, besides buying a different board?
Think you might be better doing that to start with
Just seems like a lot of things could go wrong there. I would think it would be better to not use the riser and my funky adapter, just seems like a lot of soldering and connections.
You would still have to solder the dummy cpu anyway. A proper funky socket you could solder into the booster and that seems like the easiest solution to me.
Re: non-socketed CPU
Posted: Mon Aug 28, 2017 4:55 pm
by IngoQ
exxos wrote: ↑Mon Aug 28, 2017 4:40 pm
just seems like a lot of soldering and connections.
That indeed it does. We are for sure way beyond what the average user could do. To be honest, I'm not really sure whether I really would like to try. But I like to know all options, before I decide. We already were a the point, where I stated, that in this special case you are pretty much screwed. The continuation is just personal stubbornness.
Maybe if I simply could order a working STE board on ebay for 20Bucks, I would do so. But there are none. In fact you hardly find any STE below 150 EUR these days. Mine was 180 EUR and in very good condition, and I consider myself lucky.
Re: non-socketed CPU
Posted: Mon Aug 28, 2017 5:02 pm
by exxos
There is another option... Not very pretty either ..
My original V1.5 booster I hacked into a STE. This was to see if it would work before I designed the STE V1 booster. You would still have to change the CPU.. and would have to isolate the 8mhz clock in and out... Not really ideal either, but thought while we throwing about ideas....
Re: non-socketed CPU
Posted: Mon Sep 11, 2017 8:41 pm
by IngoQ
Today a neat little package package arrived... no cat, but STE booster and TOS-Kit
Did I mention that I am stubborn?
Re: non-socketed CPU
Posted: Mon Sep 11, 2017 9:34 pm
by exxos
IngoQ wrote: ↑Mon Sep 11, 2017 8:41 pm
Today a neat little package package arrived... no cat, but STE booster and TOS-Kit
cool. My girlfriend gives me little packages, they normally little bags of cat poo.
IngoQ wrote: ↑Mon Sep 11, 2017 8:41 pm
Did I mention that I am stubborn?
You need to be stubborn with retro computing.
Re: non-socketed CPU
Posted: Mon Oct 09, 2017 4:14 pm
by IngoQ
Just stumbled upon this:
- How_to_solder_castallated_via_tutorial-23.jpg (425.97 KiB) Viewed 7959 times
Never seen this before, apparently you can use plated half holes at the edges of your PCB and solder these to SMT pads...
Now this is how my STE board looked like after removing the CPU:
- plcc-pads.jpg (650.73 KiB) Viewed 7959 times
So in theory, you could make a PCB that could be soldered directly on the STEs mainboard.
Sadly the resulting PCB would be smaller than the funky pinout at the bottom of the booster, so simply having pin headers sticking upwards would not work. Unless you use a second PCB...
Re: non-socketed CPU
Posted: Mon Oct 09, 2017 4:28 pm
by exxos
IngoQ wrote: ↑Mon Oct 09, 2017 4:14 pm
Never seen this before, apparently you can use plated half holes at the edges of your PCB and solder these to SMT pads...
Probably just normal vias and they cut the pcb "mid hole".
IngoQ wrote: ↑Mon Oct 09, 2017 4:14 pm
So in theory, you could make a PCB that could be soldered directly on the STEs mainboard.
Sadly the resulting PCB would be smaller than the funky pinout at the bottom of the booster, so simply having pin headers sticking upwards would not work. Unless you use a second PCB...
I think this is getting overcomplicated now.. I think as suggested previously, the V1.5 booster may be a better option.
Saying that, if you soldered the HC CPU direct to the motherboard, and just isolated the clock and run it via the booster PCB, then you do not need many more signals linked to the booster PCB in order for it to work.
Basically just RW, BG, BR, BGACK, AS.
If you just wire linked these direct to the CPU, or anywhere really on the motherboard, and rooted these to the CPU socket on the booster, these are the only wires you really need to route. Aside from the CPU CLK way would need to probably lift the pin on the CPU itself to isolate it, run that to the booster socket, and then the remaining pad on the motherboard is your 8 MHz CLK where you run to the booster also.
This way you are only needing to break one connection, and solder five wires not the whole CPU.
Also you will need to change the resistor packs on the motherboard for 2.2K ones, as the ones on the booster board will be isolated from the CPU.
I think overall this would be a lot easier option for you..