SMJ320VC5416 Datasheet, PDF (19/92 Pages) Texas Instruments – Fixed-Point Digital Signal Processor

Introduction
Table 2–2. Signal Descriptions (Continued)
TERMINAL
NAME
I/O^†
DESCRIPTION
TEST PINS
TCK^‡¶
TDI^¶
IEEE standard 1149.1 test clock. TCK is normally a free-running clock signal with a 50% duty cycle. The changes
I
on test access port (TAP) of input signals TMS and TDI are clocked into the TAP controller, instruction register,
or selected test data register on the rising edge of TCK. Changes at the TAP output signal (TDO) occur on the
falling edge of TCK.
I
IEEE standard 1149.1 test data input. Pin with internal pullup device. TDI is clocked into the selected register
(instruction or data) on a rising edge of TCK.
TDO
IEEE standard 1149.1 test data output. The contents of the selected register (instruction or data) are shifted out
O/Z of TDO on the falling edge of TCK. TDO is in the high-impedance state except when the scanning of data is in
progress. TDO also goes into the high-impedance state when OFF is low.
TMS^¶
I
IEEE standard 1149.1 test mode select. Pin with internal pullup device. This serial control input is clocked into
the TAP controller on the rising edge of TCK.
TRST#
IEEE standard 1149.1 test reset. TRST, when high, gives the IEEE standard 1149.1 scan system control of the
I
operations of the device. If TRST is not connected or driven low, the device operates in its functional mode, and
the IEEE standard 1149.1 signals are ignored. Pin with internal pulldown device.
EMU0
I/O/Z
Emulator 0 pin. When TRST is driven low, EMU0 must be high for activation of the OFF condition. When TRST
is driven high, EMU0 is used as an interrupt to or from the emulator system and is defined as input/output by way
of the IEEE standard 1149.1 scan system.
EMU1/OFF
I/O/Z
Emulator 1 pin/disable all outputs. When TRST is driven high, EMU1/OFF is used as an interrupt to or from the
emulator system and is defined as input/output by way of IEEE standard 1149.1 scan system. When TRST is
driven low, EMU1/OFF is configured as OFF. The EMU1/OFF signal, when active low, puts all output drivers into
the high-impedance state. Note that OFF is used exclusively for testing and emulation purposes (not for
multiprocessing applications). Therefore, for the OFF condition, the following apply:
TRST = low,
EMU0 = high
EMU1/OFF = low
† _{I = Input, O = Output, Z = High-impedance, S = Supply}
‡ _{These pins have Schmitt trigger inputs.}
§ _{This pin has an internal bus holder controlled by way of the BSCR register.}
¶ _{This pin has an internal pullup resistor.}
# _{This pin has an internal pulldown resistor.}
April 2003 – Revised July 2003
SGUS035A
9