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User port reset

Hi guys, my first post here.
 
I recently built one of these http://pasilassila.blogspot.fi/2014/06/switchless-jiffydos-for-c64.html adapting it for for my flat C128.
I didn't have to build the adaptor part because the C128 already has 28 pin sockets for the Kernal and C64-Kernal/BASIC.
I just lifted pin 27(A14) of a couple 28pin sockects and attached a wire to toggle between JiffyDOS and the standard Kernals of both C128 & C64 modes.
 
I originally connected it to the RESET (pin 3) of the user port, thinking that it functioned like the C64/VIC20 since they all have similar user ports.
I bought my C128 new the year it came out and I don't believe I've ever tried to reset it through the user port because it has a built-in reset switch.
 
But it didn't work, grounding pin 3 of the user port has no effect, and the device obviously didn't detect the RESET signal from the user port.
I had to run a long wire to the right side of the board and attach it to the resistor next to the reset switch. There might be a closer point, but I havn't found it yet.
 
Is this normal behavior for the C128?
If the user port RESET doesn't do anything wouldn't that cause problems for other devices that attach to the user port?

I haven't open my C128 to

I haven't open my C128 to look and verify this, but according to the schematics I have, Pin 3 of the User port (Reset) is connected to a line /EXTRES.  This line has a pasive pull-up and is "driven" by 7407 (pin 10 of U57) which is open-collector... and the only place the line goes is to the serial bus.  So grounding /RES on the user port should reset all disk drives (printers, etc.), but that is all.
The "real" internal /RES can be found on the corresponding pin 11 of U57.  Maybe this is closer for you?


I'm kupo for Kupo nuts!

Two reset lines, that makes

Two reset lines, that makes sense.
I'll have to give U57 a try, it does look closer.
Thanks.

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