Figure 12-19 Pushed Operations Overview - ARM Cortex-M3 Technical Reference Manual

Debug Port
12.4.5 Pushed compare and pushed verify operations
12-44
Both SW-DP and JTAG-DP Debug Ports support pushed operations, where the value
written as an AP transaction is used at the DP level to compare against a target read:
• the debugger writes a value as an AP transaction
• the DP performs a read from the AP
• the DP compares the two values and updates the Sticky Compare flag,
STICKYCMP, in the DP Control/Status register, based on the result of the
comparison:
— pushed compare sets STICKYCMP to b1 if the values match
— pushed verify sets STICKYCMP to b1 if the values do not match.
Whenever the STICKYCMP bit is set, on detection of a valid comparison, any
outstanding transaction repeats are cancelled.
For more information see The Control/Status Register, CTRL/STAT on
page 12-53.
The DP includes a byte lane mask, so that the compare can be restricted to particular
bytes in the word. This mask is set using the MASKLANE bits in the Control/Status
register. For more information about this masking see MASKLANE and the bit masking
of the pushed compare and pushed verify operations on page 12-56.
Figure 12-19 gives an overview of the pushed operations.
Copyright © 2005, 2006 ARM Limited. All rights reserved.

Figure 12-19 Pushed operations overview

ARM DDI 0337B