MPC563XM Reference Manual, Rev. 1
Freescale Semiconductor
1367
Preliminary—Subject to Change Without Notice
32.3
External Signal Description
32.3.1
Overview
The NPC pin interface provides for the transmission of messages from Nexus blocks to the external
development tools and for access to Nexus client registers. The NPC pin definition is outlined in
.
32.3.2
Detailed Signal Descriptions
This section describes each of the signals listed in
in more detail.Note that the JTAG test clock
(TCK) input from the pin is not a direct input to the NPC. The NPC requires two separate input clocks for
TCK clocked logic, one for posedge (rising edge TCK) logic and one for negedge (falling edge TCK)
logic. Both clocks are derived from the pin TCK, and generated external to the NPC.
32.3.2.1
EVTO_B - Event Out
Event Out (EVTO) is an output pin that is asserted upon breakpoint occurrence to provide breakpoint
status indication. The EVTO output of the NPC is generated based on the values of the individual EVTO
signals from all Nexus blocks that implement the signal.
32.3.2.2
JCOMP - JTAG Compliancy
The JCOMP signal provides the ability to share the TAP. The NPC TAP controller is enabled when
JCOMP is set to the NPC enable encoding, otherwise the NPC TAP controller remains in reset.
Table 32-3. NPC Signal Properties
Name
Port
Function
Reset State
Pull
1
1
The pull is not implemented in this block. Pullup/pulldown devices are implemented in the pads.
EVTO_B
Auxiliary
Event Out pin
0b1
—
JCOMP
JTAG
JTAG Compliancy and TAP Sharing Control
—
Down
MDO
Auxiliary
Message Data Out pins
0
2
2
Following a power-on reset, MDO[0] remains asserted until power-on reset is exited and the system clock
achieves lock.
—
MSEO
Auxiliary
Message Start/End Out pins
0b11
—
TCK
JTAG
Test Clock Input
—
Down
TDI
JTAG
Test Data Input
—
Up
TDO
JTAG
Test Data Output
High Z
3
3
TDO output buffer enable is negated when the NPC is not in the Shift-IR or Shift-DR states. A weak pull may
be implemented on TDO at the SoC level.
—
TMS
JTAG
Test Mode Select Input
—
Up