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IAR Embedded Workbench for Arm 9.70.x

Registers window

In this section:

What do you want to do?

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The Registers windows are available from the View menu.

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These windows give an up-to-date display of the contents of the processor registers and special function registers, and allow you to edit the contents of some of the registers. Optionally, you can choose to load either predefined register groups or your own user-defined groups.

You can open up to four instances of this window, which is convenient for keeping track of different register groups.

To enable predefined register groups:

  1. Select a device description file that suits your device, see Selecting a device description file. These files contain predefined register groups.

  2. Display the registers of a register group by selecting it from the Group drop-down menu on the toolbar, or by right-clicking in the window and choosing View Group from the context menu.

    For information about creating your own user-defined register groups, see Defining application-specific register groups.

Requirements

Can be used with all C-SPY debugger drivers and debug probes.

Toolbar

The toolbar contains:

Find

Specify the name, or part of a name, of a register (or group) that you want to find. Press the Enter key and the first matching register, or group with a matching register, is displayed. User-defined register groups are not searched. The search box preserves a history of previous searches. To repeat a search, select it from the search history and press Enter.

Group

Selects which predefined register group to display. By default, there are two register groups in the debugger. If some of your SFRs are missing, you can register your own SFRs in a Custom group, see SFR Setup window.

Current CPU Registers contains the registers that are available in the current processor mode.

CPU Registers contains both the current registers and their banked counterparts available in other processor modes.

Additional register groups are predefined in the device description files—available in the arm\config directory—that make all SFR registers available in the Registers windows. The device description file contains a section that defines the special function registers and their groups.

Display area

Displays registers and their values. Some registers are expandable, which means that the register contains interesting bits or subgroups of bits.

If you drag a numerical value, a valid expression, or a register name from another part of the IDE to an editable value cell in a Registers window, the value will be changed to that of what you dragged. If you drop a register name somewhere else in the window, the window contents will change to display the first register group where this register is found.

Name

The name of the register.

Value

The current value of the register. Every time C-SPY stops, a value that has changed since the last stop is highlighted. Some of the registers are editable. To edit the contents of an editable register, click on the register and modify its value. Press Esc to cancel the change.

To change the display format of the value, right-click on the register and choose Format from the context menu.

Access

The access type of the register. Some of the registers are read-only, while others are write-only.

For the C-SPY Simulator (and some C-SPY hardware debugger drivers), these additional support registers are available in the CPU Registers group:

CYCLECOUNTER

Cleared when an application is started or reset, and is incremented with the number of used cycles during execution.

CCSTEP

Shows the number of used cycles during the last performed C/C++ source or assembler step.

CCTIMER1 and CCTIMER2

Two trip counts that can be cleared manually at any given time. They are incremented with the number of used cycles during execution.

Context menu

This context menu is available:

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These commands are available:

View Group

Selects which predefined register group to display.

View User Group

Selects which user-defined register group to display. For information about creating your own user-defined register groups, see Defining application-specific register groups.

Format

Changes the display format for the contents of the register you clicked on. The display format setting affects different types of registers in different ways. Your selection of display format is saved between debug sessions.

Open User Groups Setup Window

Opens a window where you can create your own user-defined register groups, see Register User Groups Setup window.

Save to File

Opens a standard Save dialog box to save the contents of the window to a tab-separated text file.

Find Next Register

Finds the predefined register or register group that comes immediately after what your search found. After the last register was found, this search wraps around and finds the first register again.

Find Previous Register

Finds the matching predefined register or register group that comes immediately before what your search found. After the first register was found, this search wraps around and finds the last register again.