Freescale Semiconductor NXP CodeWarrior USB TAP, Руководство пользователя

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JTAG/COP Connector Information
24 USB TAP Users Guide
4 TRST Must be wired to the target processor. The USB TAP
emulator drives the TRST output with up to 50mA. To gain
control of the processor, the USB TAP emulator negates
TRST approximately 250 milliseconds before negation of
HRST. This allows the USB TAP emulator to issue COP
commands through the JTAG/COP interface and gain control
of the processor upon negation of HRST. The TRST trace run
should be kept short and maintain a "two-signal-width"
spacing from any other parallel dynamic signal trace.
5 HALTED Need not be wired to the target. The USB TAP emulator does
not currently use this signal.
6 TGT PWR Must be wired to the target. The USB TAP emulator uses this
signal to determine if power is applied to the target. This
signal is also used as a voltage reference for the signals
driven by the USB TAP emulator (CKSI, TRST, TCK, TMS,
TDI).
TGT PWR (pin 6) should be connected to target Vcc through
a 1KOhm pull-up.
7 TCK 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.
8 CKSI Need not be wired to the target.
The USB TAP does not currently use this signal.
9 TMS Must be wired to the target processor. The USB TAP drives
the TMS output with up to 50mA. TMS should be kept as
short as possible and maintain a "two signal width" spacing
from any other parallel dynamic signal trace. TMS should
have a termination option at the processor.
10 No Connect Not required for emulation
11 SRST May be wired to the target processor. During reset, the USB
TAP drives SRST to ground through a 100Ohm resistor.
12 No Connect Not required for emulation
Table A.2 CodeWarrior USB TAP for JTAG/COP Signal Recommendations/Requirements
JTAG/
COP
Pin Signal
Mnemonic Requirement
U SB_TA P.book Page 24 Thursday, N ovem ber 10, 2005 2:27 PM