
Enhanced Time Processing Unit (eTPU2)
MPC5644A Microcontroller Reference Manual, Rev. 6
962
Freescale Semiconductor
24.5.10 Test and Development Support
24.5.10.1 Overview
Following sections describe several features available to support development and test. Most debug
features, described in
Section 24.5.10.2, Development support features
, are accessible through a separate
debug bus, and are not available through registers in the standard eTPU memory map. The details of the
access to this interface are MCU-dependent, but a separate IP block, called NDEDI, is provided so that
these features are accessible by a Nexus interface. IP-bus Green line device debug request can also be used
to put microengines in halt state. Conditions for the assertion of this line are also MCU-dependent.
Section 24.5.10.3, Test support features
, describes embedded test features: the Multiple Input Signature
Calculator (MISC) is an SCM test feature accessible through registers ETPU_MCR and
ETPU_MISCCMPR (see
Section 24.4.2, System configuration registers
). MISC allows SCM test “on the
fly, that is, while eTPU is running, with no impact on eTPU functionality or performance.
24.5.10.2 Development support features
24.5.10.2.1
Internal Debug Interface and Nexus Class 3 support
eTPU provides an Internal Debug Interface that exports real-time microengine states and values, including
breakpoint/watchpoint information. It also provides inputs for breakpoint request from other blocks or
outside MCU.
NDEDI is an IP block designed to support Nexus functionality for the eTPU. When Internal Debug
Interface is connected to an NDEDI block, the MCU can provide Nexus Class 3 debug interface. Nexus is
a development support external interface defined by the
IEEE standard ISTO 5001-1999
.
Some of the next subsections describe debug features provided by the Internal Debug Interface combined
with the NDEDI block. NDEDI can be replaced by other block providing a different programming
interface, such as a register debug interface, for instance.
24.5.10.2.2
Microengine halt state
Halt is a microengine state where it suspends execution during a thread, or does not start executing a
scheduled thread from idle state. While Idle State is entered from END execution without any other
scheduled thread, microengine enters Halt State by any of the following events:
•
Execution of the HALT microinstruction (software breakpoint).
•
External halt request through the Debug Interface (includes Nexus breakpoint request via EVTI
input pin (see
Section 24.5.10.2.1, Internal Debug Interface and Nexus Class 3 support
).
•
The other engine enters halt state and they are configured to halt simultaneously (bit HTWIN is
asserted via Nexus Interface).
•
IPI Green line device debug request assertion and NDEDI register NDEDIETPUx_DC field
CBI = 1. If same register’s field CBT = 1, microengine halts at the next time-slot boundary, if
CBT = 0 it halts immediately. As a particular case, microengines come halted out of reset if device
debug request is asserted, since CBI reset value is 1. Microengine does not execute out of reset,
Summary of Contents for MPC5644A
Page 2: ...MPC5644A Microcontroller Reference Manual Rev 6 2 Freescale Semiconductor...
Page 24: ...MPC5644A Microcontroller Reference Manual Rev 6 24 Freescale Semiconductor...
Page 26: ...MPC5644A Microcontroller Reference Manual Rev 6 26 Freescale Semiconductor...
Page 52: ...Introduction MPC5644A Microcontroller Reference Manual Rev 6 52 Freescale Semiconductor...
Page 56: ...Memory Map MPC5644A Microcontroller Reference Manual Rev 6 56 Freescale Semiconductor...
Page 1228: ...Decimation Filter MPC5644A Microcontroller Reference Manual Rev 6 1228 Freescale Semiconductor...
Page 1440: ...FlexCAN Module MPC5644A Microcontroller Reference Manual Rev 6 1440 Freescale Semiconductor...