Freescale Semiconductor NXP CodeWarrior USB TAP, Руководство пользователя

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OnCE Connector Information
39 USB TAP Users Guide
Table D.2 CodeWarrior USB TAP for OnCE Signal Recommendations and Requirements
OnCE
Pin Signal
Mnemonic Requirement
1 TDI Must be wired to the target processor. The USB TAP
emulator drives the TDI output with up to 50 mA. The TDI
trace should be kept short and maintain a "two-signal-width"
spacing from any other parallel dynamic signal trace. TDI
should have an RC termination option at the processor.
2 GND Must be wired to the USB TAP. GND is connected directly
to the USB TAP ground inside the USB TAP.
3 TDO Must be wired to the target processor. TDO is an output
from the target processor and input to the USB TAP
emulator. The TDO trace run should be kept short and
maintain a "two-signal-width" spacing from any other
parallel dynamic signal trace. TDO should have a series
termination resistor located near the target processor.
4 GND Must be wired to the USB TAP. GND is connected directly
to the USB TAP ground inside the USB TAP.
5 TCK Must be wired to the target processor. The USB TAP
emulator drives the TCK output with up to 50 mA. The TCK
trace run should be kept as short as possible and maintain
a “two-signal-width” spacing from any other parallel
dynamic signal trace.
6
GND
Must be wired to the USB TAP. GND is connected directly
to the USB TAP ground inside the USB TAP.
7 Reserved Not required for emulation.
8 No-Connect/
Key Not required for emulation. Pin 8 should be clipped on the
target OnCE header.
9 RESET Must be wired to the target processor. The USB TAP drives
the RESET output with 50mA. During reset, the USB TAP
drives RESET to ground through a 100Ohm resistor.
10 TMS Must be wired to the target processor. The USB TAP
emulator drives the TCK output with up to 50mA. The TCK
trace run should be kept as short as possible and maintain
a “two-signal-width” spacing from any other parallel
dynamic signal trace.
U SB_TA P.book Page 39 Thursday, N ovem ber 10, 2005 2:27 PM