User`s manual

4.4 Flash ROM (System ROM)

4.4.3 Flash ROM Access

The ﬂash ROM can be viewed as two banks of 512KB each. At power-up,

the lower 512KB bank is accessed using the address range 3 FFF8 0000 to

3 FFFF FFFF.

Setting address bit 19 will allow you to access the higher 512KB of ﬂash ROM.

Write a 1 to the register at address 800 to set address bit 19. Manually deposit

a 1 to address 1 C001 0000 or enter the following command from the debug

monitor:

> wb 800 1

The address range for the higher bank is 3 FFF8 0000 to 3 FFFF FFFF, the

same as for the lower bank. Access is now to the higher bank and will continue

until the AlphaPC64 is reset or a 0 is written to the register at address 800.

Note

The update-enable jumper must be installed from pin J16-2 to pin

J16-3 to enable writing to the ﬂash ROM. See connector J16 in

Table 2–3.

4–14 Functional Elements