Hardware Description

The configuration block in the development chip samples the state of the HDATAMx pins while the rest of the chip is held in reset. The state of these pins is stored and used to drive configuration signals within the chip and to define the operating mode of the chip when reset is released. For more detail on the configuration signals, see Configuration registers SYS_CFGDATAx on page 4-25 and the ARM926EJ-S Development Chip Reference Manual.

Note

For details on configuring the clocks, see ARM926EJ-S PXP Development Chip clocks on page 3-39.

Changing the ARM926EJ-S PXP Development Chip configuration at runtime

To change the configuration of the ARM926EJ-S PXP Development Chip:

1.Program the appropriate values in the SYS_CFGDATAx registers, see Configuration registers SYS_CFGDATAx on page 4-25.

2.Perform a configuration reset of the PB926EJ-S, but do not power-cycle, by either:

pressing the DEVCHIP RECONFIG pushbutton (next to the blue LED)

programming the reset-depth register to level 2 (see Reset Control Register, SYS_RESETCTL on page 4-31) and then performing a normal reset from software, the reset pushbutton, or JTAG.

Restoring the default configuration

To restore the default processor configuration, power-cycle the PB926EJ-S or press the FPGA CONFIG pushbutton (next to the yellow LED).

3.1.3AHB bridges and the bus matrix

The ARM926EJ-S PXP Development Chip is based on the ARM926EJ-S PrimeXSys Platform. The PrimeXSys Platform contains a multi-layer AHB bus matrix that routes the signals from six masters to a number of slaves. These six masters are CPU-D, CPU-I, DMA port0, DMA port1, CLCDC, Expansion master. The slaves include internal AHB-APB bridges, the MPMC and SSMC memory controllers and three expansion slaves, one of which is the internal AHB monitor block. (See Figure 3-1 on page 3-4).

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ARM DUI 0224I

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ARM ARM DUI 0224I manual Restoring the default configuration, AHB bridges and the bus matrix