PC755 datasheet(36/50 Pages) ATMEL

36 / 50 page

PC755/745

2138D–HIREL–06/03

The COP header shown in Figure 24 adds many benefits—breakpoints, watchpoints,

are possible through this interface – and can be as inexpensive as an unpopulated foot-

print for a header to be added when needed.

System design information

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 connector typically has pin 14 removed as a connector key.

Figure 24 shows the COP connector diagram.

Figure 24. COP Connector Diagram

There is no standardized way to number the COP header shown in Figure 24; conse-

quently, 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 one (as with an IC).

Regardless of the numbering, the signal placement recommended in Figure 24 is com-

mon to all known emulators.

The QACK signal shown in Table 17 is usually hooked up to the PCI bridge chip in a

system and is an input to the PC755 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 PC755 must see this signal asserted (pulled down). While shown on

the COP header, not all emulator products drive this signal. To preserve correct power

down operation, QACK should be merged so that it also can be driven by the PCI

bridge.

TOP VIEW

KEY

No pin

Pins 10, 12 and 14 are no-connects.

Pin 14 is not physically present

PC755 Datasheet(PDF) 36 Page - ATMEL Corporation