6.2. Write Buffer Operation

When the CPU performs a write operation, the translation entry for that address is inspected and the state of the B bit determines the subsequent action. If the write buffer is disabled via the ARM720T Control Register, buffered writes are treated in the same way as unbuffered writes.

To enable the write buffer
  1. Ensure the MMU is enabled by setting bit 0 in the Control Register.

  2. Enable the write buffer by setting bit 3 in the Control Register. The MMU and write buffer may be enabled simultaneously with a single write to the Control Register.

To disable the write buffer
  1. Clear bit 3 in the Control Register.

Note

Any writes already in the write buffer complete normally.

Copyright © 1997, 1998 ARM Limited. All rights reserved.DDI 0087E
Non-Confidential