Coprocessors

5.2.13Register 14 – Debug Support (Breakpoints)

The SA-1100 supports address and data breakpoints through register 14 of coprocessor 15. The instruction formats follow. For a description of the breakpoint operation, see Chapter 15, “Debug Support” . The following table shows the OPC_2 and CRm field encodings used to access the address and data breakpoints.

 

Function

OPC_2

CRm

 

 

 

Access data breakpoint address register (DBAR).

0b000

0b0000

 

 

 

Access data breakpoint value register (DBVR).

0b000

0b0001

 

 

 

Access data breakpoint mask register (DBMR).

0b000

0b0010

 

 

 

Load data breakpoint control register (DBCR).

0b000

0b0011

-----------------------------------------------------------------

 

 

DBCR Bit

Action

 

 

-----------------------------------------------------------------

 

 

lw

0 = Disable load watch

 

 

 

1 = Enable load watch

 

 

saw

0 = Disable store address watch

 

 

 

1 = Enable store address watch

 

 

sdw

0 = Disable store data watch

 

 

 

1 = Enable store data watch

 

 

 

 

 

Write instruction breakpoint address and control register (IBCR).

0b000

0b1000

Low-order address bit is the address break enable/disable bit.

 

 

Register not readable.

 

 

 

 

 

 

The DBCR register is a 3-bit register used to control the enabling and disabling of the data breakpoints. Bits 0..2 are valid and positioned as shown below. Bits 3..31 are reserved. These bits read as zeros and writes have no effect.

31

Reserved

2 1 0

sdw saw lw

The IBCR is a write-only register used to load an address breakpoint address and to set an enable bit for the function. If an address is loaded with bit 0 (E) set, then the address is enabled as a breakpoint. If bit zero is cleared, then the breakpoint is disabled. Bit 1 is reserved and should be written to zero.

31

2

1

0

Instruction Address Breakpoint Value

r E

5-8

SA-1100 Developer’s Manual

Page 52
Image 52
Intel SA-1100 manual Register 14 Debug Support Breakpoints, Dbcr Bit Action