
HMS30C7202N
2004 MagnaChip Semiconductor Ltd. All Rights Reserved. Version 1.1
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11
11.1
Overview
The HMS30C7202 has built-in features that enable debug and test in a number of different contexts. Firstly,
there are circuit structures to help with software development. Secondly, the device contains boundary scan
cells for circuit board test. Finally, the device contains some special test modes that enable the generation
production patterns for the device itself.
11.2
Software Development Debug and Test Interface
The ARM720T and Piccolo processors incorporated inside HMS30C7202 contain hardware extensions for
advanced debugging features. These are intended to ease user development and debugging of application
software, operating systems, and the hardware itself.
Full details of the debug interfaces and their programming can be found in
ARM720T Data Sheet
(ARM DDI-
0087) and
Piccolo Data Sheet
(ARM DDI-0128). The MultiICE product enables the ARM720T and Piccolo
macrocells to be debugged in one environment. Refer to
Guide to MultiICE
(ARM DUI-0048).
11.3
Test Access Port and Boundary-Scan
HMS30C7202 contains full boundary scan on its inputs and outputs to help with circuit board test. This
supports both INTEST and EXTEST, allowing patterns to be applied serially to the HMS30C7202 when fixed
in a board and for full circuit board connection respectively. The boundary-scan interface conforms to the IEEE
Std. 1149.1- 1990, Standard Test Access Port and Boundary-Scan Architecture. (Please refer to this standard
for an explanation of the terms used in this section and for a description of the TAP controller states.) The
boundary-scan interface provides a means of testing the core of the device when it is fitted to a circuit board,
and a means of driving and sampling all the external pins of the device irrespective of the core state. This
latter function permits testing of both the device's electrical connections to the circuit board, and (in
conjunction with other devices on the circuit board having a similar interface) testing the integrity of the circuit
board connections between devices. The interface intercepts all external connections within the device, and
each such “cell” is then connected together to form a serial register (the boundary scan register). The whole
interface is controlled via 5 dedicated pins:
TDI
,
TMS
,
TCK
,
nTRST
and
TDO
.
Figure 11-1: Test Access Port
(TAP) Controller State Transitions
shows the state transitions that occur in the TAP controller.
DEBUG AND TEST INTERFACE