Debug Support
ARM DDI0145B
Copyright © 1998, 1999 ARM Limited. All rights reserved.
5-11
5.4
Scan chains and JTAG interface
There are three scan chains inside the ARM9TDMI. These allow testing, debugging and
programming of the EmbeddedICE macrocell watchpoint units. The scan chains are
controlled by a JTAG-style
Test Access Port
(TAP) controller. In addition, support is
provided for an optional fourth scan chain. This is intended to be used for an external
boundary scan chain around the pads of a packaged device. The signals provided for this
scan chain are described on
The three scan chains of the ARM9TDMI are referred to as scan chain 0, 1 and 2.
Note
The ARM9TDMI TAP controller supports 32 scan chains. Scan chains 0 to 15 have
been reserved for use by ARM. Any extension scan chains should be implemented in
the remaining space. The
SCREG[4:0]
signals indicate which scan chain is being
accessed.
Содержание ARM9TDMI
Страница 1: ...Copyright 1998 1999 ARM Limited All rights reserved ARM DDI0145B ARM9TDMI Technical Reference Manual ...
Страница 6: ...Contents vi Copyright 1998 1999 ARM Limited All rights reserved ARM DDI0145B ...
Страница 12: ...Preface xii Copyright 1998 1999 ARM Limited All rights reserved ARM DDI0145B ...
Страница 16: ...Introduction 1 4 Copyright 1998 1999 ARM Limited All rights reserved ARM DDI0145B ...
Страница 22: ...Programmer s Model 2 6 Copyright 1998 1999 ARM Limited All rights reserved ARM DDI0145B ...
Страница 36: ...ARM9TDMI Processor Core Memory Interface 3 14 Copyright 1998 1999 ARM Limited All rights reserved ARM DDI0145B ...
Страница 54: ...ARM9TDMI Coprocessor Interface 4 18 Copyright 1998 1999 ARM Limited All rights reserved ARM DDI0145B ...
Страница 110: ...Test Issues 6 6 Copyright 1998 1999 ARM Limited All rights reserved ARM DDI0145B ...
Страница 138: ...ARM9TDMI AC Characteristics 8 20 Copyright 1998 1999 ARM Limited All rights reserved ARM DDI0145B ...
Страница 150: ...ARM9TDMI Signal Descriptions A 12 Copyright 1998 1999 ARM Limited All rights reserved ARM DDI0145B ...
Страница 154: ...Index Index 4 Copyright 1998 1999 ARM Limited All rights reserved ARM DDI0145B ...