22 SBC330 3U VPX Single Board Computer
Publication No. SBC330-0HH/3
4.4.1 JTAG
4.4.2 AMP/SMP Mode selection
To
operate
the
SBC330
in
Asymmetric
Multiprocessing
(AMP)
mode,
P12
pin
1
and
pin
2
must
be
linked.
In
AMP
mode,
the
two
cores
may
run
either
different
operating
systems
or
different
versions
of
the
same
operating
system.
To
allow
this,
the
MPC8641D
processor
provides
the
ability
to
offset
Core
1
accesses
to
the
bottom
of
RAM
by
256
MBytes
(addresses
0x000
0000
to
0x1000
0000
are
offset
to
0x1000
0000
to
0x2000
0000).
This
allows
both
processing
cores
to
maintain
separate
stacks
and
private
memory
without
any
software
intervention.
This
is
the
default
mode
selected
with
this
link
not
fitted.
When
the
two
processors
are
operating
in
Symmetric
Multiprocessing
(SMP)
mode,
this
feature
is
not
desirable
as
both
processors
need
to
share
the
same
memory
space.
Table 4-3 JTAG Jumpers on Header P12
P12 Pins
Function
Action when fitted
Pin 1 & pin 2
1) Isolate ispPAC device from JTAG.
2) Select AMP/SMP mode.
PWR MAN isolated.
AMP mode selected.
Pin 3 & pin 4
Processor JTAG: chain or Emulator
Processor in chain
Pin 5 & pin 6
Binary combination with pins 7 & 8
See next table
Pin 7 & pin 8
Binary combination with pins 5 & 6
See next table
Table 4-4 JTAG Multiplex Jumpers on P12 Header
Pins 5-6
Pins 7-8
Binary
Function
Not fitted
Not fitted
00
TDO from chain – excluding processor
Not fitted
Fitted
01
TDO from (FPGA-CPLD only) chain
Fitted
Not fitted
10
TDO from ispPAC Power Manager
Fitted
Fitted
11
TDO from chain including Processor
• To
program
ispPWR
‐
PAC:
Link
P12
pin
5
to
pin
6
only
• To
program
Lattice
FPGA
and
CPLD:
Link
P12
pins
1
to
2
and
7
to
8
only
• To
test
all
JTAG
chain:
Link
P12
pins
1
to
2,
3
to
4,
5
to
6
and
7
to
8
• To
test
chain
without
processor:
Link
P12
pin
1
to
pin
2
only
Table 4-5 P12 AMP/SMP Mode
Pin 1 to Pin 2 Setting
Function
Not linked
SMP Mode. No core 1 addressing offset
Linked
AMP Mode. Core 1 has 256 MByte memory offset