No Clock On 128D

[sacmame]

Hey there, new here, just been dusting off my old 128d that I ran a bbs off of 20 years ago..  Just noticed that the bbs prg I use (cnet 128) the clock isn't updating at all, actually anything that uses a timer won't work.  Same seems to be true in c-64 mode as well.

What area/chip should I be looking at replacing to get the area that software uses as a clock back up?

thanks
-sac

[hydrophilic]

It's probably one of the 6526 CIAs.  The one for keyboard/joystick/fast-serial is labeled U1 on the board.  The second, for RS-232 and slow-serial is labeled U4 on the board.  I'm not familiar with the layout of the 'D' model, but flat 128s have U1 at the far right by the joystick ports and U4 at the back left by the user port.