Hardware Description

3.1.5AHB monitor

The ARM926EJ-S PXP Development Chip contains a multi-layer AHB system to provide high bandwidth connectivity between the various bus masters and slaves both within and outside the ARM926EJ-S PXP Development Chip.

The AHB layer monitors observe the activity on their respective bus signals to produce real-time information that is exported off-chip to a logic analyzer.

The AHB monitor also contains event counters that monitor bus transactions. The event counters can be accessed through the both the ARM DATA AHB and ARM AHB S buses. The event counters provide a simple mechanism for monitoring bus utilization.

The AHB debug port consists of 33 output pins that export status data packets at the AHB clock rate. A localized clock is exported on AHBMONITOR[33]. The interface between the development chip and the debug connector is shown in Figure 3-7.

The base address of the AHB monitor is at 0x101D0000.

Figure 3-7 AHB monitor connection

See the ARM926EJ-S Reference Manual and AHB monitor on page 4-41.

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ARM DUI 0224I

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ARM ARM DUI 0224I manual AHB monitor connection