TASKING iSYSTEM ST SPC58, Руководство пользователя по оборудованию

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Configuration
J1: Target reset configuration
Jumper J1 connects the reset line and the target reset line. By default, J1 is populated.
When having problems establishing the initial debug session with the Emulation Adapter (EA),
try to remove J1 and see if it makes any difference.
J2 and J3: Clock source configuration
Jumpers J2 and J3 select external clock source (XOSC) for the emulation device. Per default,
both jumpers are set to position 1-2, which yields the external clock (XOSC) source being used
from the Target board.
If an oscillator in the Target is not an option and the target crystal doesn’t oscillate in conjunc-
tion with the EA, the EA can also provide the external clock (XOSC) source by setting jumpers J2
and J3 in position 2-3. In this case, a crystal circuit must be built on the EA.
Note that the EA 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 microcontrol-
ler.
It can happen that the target crystal does not oscillate in conjunction with the EA since
clock lines (XTAL, EXTAL) between the target crystal and the emulation device on the
EA become too long, inevitably too much affecting the impedance of the crystal cir-
cuit. If a “standalone” oscillator is used instead of the crystal circuit, no problems are
expected.
The crystal packed separately in the antistatic bag comes along the Emulation Ad-
apter. It can be used to feed an external clock source (XOSC) to the emulation device
by inserting the crystal into the Q1 socket. If a different clock frequency is required, use
suitable crystal and insert it into the Q1 socket.
The emulation adapters of revision A1 were delivered with a 40 MHz crystal, while the
adapters of revision A2 or higher are delivered with a 20 MHz crystal.
Crystal Q1 is located in the corner of the EA , next to the 38-pin Mictor connector P1 and per de-
fault not populated: