Configuration
J1: Target reset configuration
Jumper J1 connects the TC234LF reset line (PORST) and the target reset line. By default J1 is
populated.
When having problems establishing the initial debug session with the emulation adapter, try to
remove J1 and see if it makes any difference.
J2 and J3: Clock source configuration
Jumpers J2 and J3 select clock source for the microcontroller on the emulation adapter.
Per default, both jumpers are set to position 1-2, which yields the clock source being used from
the target.
Note that the emulation adapter may not operate when crystal circuit is used in the
target. Typical design guideline is that the crystal should be as close as possible to the
microcontroller. However, it may happen that the target crystal may not oscillate in
conjunction with the emulation adapter since clock lines (XTAL1, XTAL2) between the
target and the emulation device on the emulation adapter can become too long, con-
sequentially affecting the impedance of the crystal circuit too much. There should be
no problem if the oscillator is used in the target.
If an oscillator in the target is not an option and the target crystal doesn’t oscillate in conjunc-
tion with the emulation adapter, clock from the emulation adapter must be used (J2 & J3 posi-
tion 2-3). In this case, a crystal circuit must be assembled on the emulation adapter.
Crystal circuit is located in the corner of the emulation adapter.
Per default 10pF capacitors are populated for C1 and C2 and the
crystal Q1 is not populated.
Note that C1 and C2 values are valid for 20MHz crystal only. If dif-
ferent crystal is used, the default 10 pF capacitors must be re-
placed with proper value.
J4 & J5: GND connecting points