PCX7457VGH1000NC Atmel, PCX7457VGH1000NC Datasheet - Page 54

• Manufacturer Part Number: PCX7457VGH1000NC
• Description: IC MPU 32BIT 1000MHZ 483CBGA
• Manufacturer: Atmel

Specifications of PCX7457VGH1000NC

• Processor Type: PowerPC 32-Bit RISC
• Speed: 1.0GHz
• Voltage: 1.1V
• Mounting Type: Surface Mount
• Package / Case: 483-CBGA
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Features: -

The COP header shown in
Figure 15-1
adds many benefits – breakpoints, watchpoints, register
and memory examination/modification, and other standard debugger features are possible
through this interface – and can be as inexpensive as an unpopulated footprint for a header to
be added when needed.
The COP interface has a standard header for connection to the target system, based on the
0.025" square-post, 0.100" centered header assembly (often called a Berg header). The con-
nector typically has pin 14 removed as a connector key.
There is no standardized way to number the COP header shown in
Figure
15-1; consequently,
many different pin numbers have been observed from emulator vendors. Some are numbered
top-to-bottom then left-to-right, while others use left-to-right then top-to-bottom, while still others
number the pins counter clockwise from pin 1 (as with an IC). Regardless of the numbering, the
signal placement recommended in
Figure 15-1
is common to all known emulators.
The QACK signal shown in
Figure 15-1
is usually connected to the PCI bridge chip in a system
and is an input to the PC7457 informing it that it can go into the quiescent state. Under normal
operation this occurs during a low-power mode selection. In order for COP to work, the PC7457
must see this signal asserted (pulled down). While shown on the COP header, not all emulator
products drive this signal. If the product does not, a pull-down resistor can be populated to
assert this signal. Additionally, some emulator products implement open-drain type outputs and
can only drive QACK asserted; for these tools, a pull-up resistor can be implemented to ensure
this signal is deasserted when it is not being driven by the tool. Note that the pull-up and pull-
down resistors on the QACK signal are mutually exclusive and it is never necessary to populate
both in a system. To preserve correct power-down operation, QACK should be merged via logic
so that it also can be driven by the PCI bridge.
PC7457
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5345D–HIREL–07/06