# 26.9. Classic API Configuration¶

This section describes configuration options related to the Classic API.

## 26.9.1. CONFIGURE_MAXIMUM_BARRIERS¶

CONSTANT:

CONFIGURE_MAXIMUM_BARRIERS

OPTION TYPE:

This configuration option is an integer define.

DEFAULT VALUE:

The default value is 0.

DESCRIPTION:

The value of this configuration option defines the maximum number of Classic API Barriers that can be concurrently active.

NOTES:

This object class can be configured in unlimited allocation mode, see Unlimited Objects.

CONSTRAINTS:

The following constraints apply to this configuration option:

• The value of the configuration option shall be greater than or equal to zero.

• The value of the configuration option shall be less than or equal to 65535.

• The value of the configuration option shall be less than or equal to a BSP-specific and application-specific value which depends on the size of the memory available to the application.

• The value of the configuration option may be defined through rtems_resource_unlimited() the enable unlimited objects for the object class, if the value passed to rtems_resource_unlimited() satisfies all other constraints of the configuration option.

## 26.9.2. CONFIGURE_MAXIMUM_MESSAGE_QUEUES¶

CONSTANT:

CONFIGURE_MAXIMUM_MESSAGE_QUEUES

OPTION TYPE:

This configuration option is an integer define.

DEFAULT VALUE:

The default value is 0.

DESCRIPTION:

The value of this configuration option defines the maximum number of Classic API Message Queues that can be concurrently active.

NOTES:

This object class can be configured in unlimited allocation mode, see Unlimited Objects. You have to account for the memory used to store the messages of each message queue, see CONFIGURE_MESSAGE_BUFFER_MEMORY.

CONSTRAINTS:

The following constraints apply to this configuration option:

• The value of the configuration option shall be greater than or equal to zero.

• The value of the configuration option shall be less than or equal to 65535.

• The value of the configuration option shall be less than or equal to a BSP-specific and application-specific value which depends on the size of the memory available to the application.

• The value of the configuration option may be defined through rtems_resource_unlimited() the enable unlimited objects for the object class, if the value passed to rtems_resource_unlimited() satisfies all other constraints of the configuration option.

## 26.9.3. CONFIGURE_MAXIMUM_PARTITIONS¶

CONSTANT:

CONFIGURE_MAXIMUM_PARTITIONS

OPTION TYPE:

This configuration option is an integer define.

DEFAULT VALUE:

The default value is 0.

DESCRIPTION:

The value of this configuration option defines the maximum number of Classic API Partitions that can be concurrently active.

NOTES:

This object class can be configured in unlimited allocation mode, see Unlimited Objects.

CONSTRAINTS:

The following constraints apply to this configuration option:

• The value of the configuration option shall be greater than or equal to zero.

• The value of the configuration option shall be less than or equal to 65535.

• The value of the configuration option shall be less than or equal to a BSP-specific and application-specific value which depends on the size of the memory available to the application.

• The value of the configuration option may be defined through rtems_resource_unlimited() the enable unlimited objects for the object class, if the value passed to rtems_resource_unlimited() satisfies all other constraints of the configuration option.

## 26.9.4. CONFIGURE_MAXIMUM_PERIODS¶

CONSTANT:

CONFIGURE_MAXIMUM_PERIODS

OPTION TYPE:

This configuration option is an integer define.

DEFAULT VALUE:

The default value is 0.

DESCRIPTION:

The value of this configuration option defines the maximum number of Classic API Periods that can be concurrently active.

NOTES:

This object class can be configured in unlimited allocation mode, see Unlimited Objects.

CONSTRAINTS:

The following constraints apply to this configuration option:

• The value of the configuration option shall be greater than or equal to zero.

• The value of the configuration option shall be less than or equal to 65535.

• The value of the configuration option shall be less than or equal to a BSP-specific and application-specific value which depends on the size of the memory available to the application.

• The value of the configuration option may be defined through rtems_resource_unlimited() the enable unlimited objects for the object class, if the value passed to rtems_resource_unlimited() satisfies all other constraints of the configuration option.

## 26.9.5. CONFIGURE_MAXIMUM_PORTS¶

CONSTANT:

CONFIGURE_MAXIMUM_PORTS

OPTION TYPE:

This configuration option is an integer define.

DEFAULT VALUE:

The default value is 0.

DESCRIPTION:

The value of this configuration option defines the maximum number of Classic API Ports that can be concurrently active.

NOTES:

This object class can be configured in unlimited allocation mode, see Unlimited Objects.

CONSTRAINTS:

The following constraints apply to this configuration option:

• The value of the configuration option shall be greater than or equal to zero.

• The value of the configuration option shall be less than or equal to 65535.

• The value of the configuration option shall be less than or equal to a BSP-specific and application-specific value which depends on the size of the memory available to the application.

• The value of the configuration option may be defined through rtems_resource_unlimited() the enable unlimited objects for the object class, if the value passed to rtems_resource_unlimited() satisfies all other constraints of the configuration option.

## 26.9.6. CONFIGURE_MAXIMUM_REGIONS¶

CONSTANT:

CONFIGURE_MAXIMUM_REGIONS

OPTION TYPE:

This configuration option is an integer define.

DEFAULT VALUE:

The default value is 0.

DESCRIPTION:

The value of this configuration option defines the maximum number of Classic API Regions that can be concurrently active.

NOTES:

This object class can be configured in unlimited allocation mode, see Unlimited Objects.

CONSTRAINTS:

The following constraints apply to this configuration option:

• The value of the configuration option shall be greater than or equal to zero.

• The value of the configuration option shall be less than or equal to 65535.

• The value of the configuration option shall be less than or equal to a BSP-specific and application-specific value which depends on the size of the memory available to the application.

• The value of the configuration option may be defined through rtems_resource_unlimited() the enable unlimited objects for the object class, if the value passed to rtems_resource_unlimited() satisfies all other constraints of the configuration option.

## 26.9.7. CONFIGURE_MAXIMUM_SEMAPHORES¶

CONSTANT:

CONFIGURE_MAXIMUM_SEMAPHORES

OPTION TYPE:

This configuration option is an integer define.

DEFAULT VALUE:

The default value is 0.

DESCRIPTION:

The value of this configuration option defines the maximum number of Classic API Semaphore that can be concurrently active.

NOTES:

This object class can be configured in unlimited allocation mode, see Unlimited Objects.

In SMP configurations, the size of a Semaphore Control Block depends on the scheduler count (see Configuration Step 3 - Scheduler Table). The semaphores using the Multiprocessor Resource Sharing Protocol (MrsP) need a ceiling priority per scheduler.

CONSTRAINTS:

The following constraints apply to this configuration option:

• The value of the configuration option shall be greater than or equal to zero.

• The value of the configuration option shall be less than or equal to 65535.

• The value of the configuration option shall be less than or equal to a BSP-specific and application-specific value which depends on the size of the memory available to the application.

• The value of the configuration option may be defined through rtems_resource_unlimited() the enable unlimited objects for the object class, if the value passed to rtems_resource_unlimited() satisfies all other constraints of the configuration option.

CONSTANT:

CONFIGURE_MAXIMUM_TASKS

OPTION TYPE:

This configuration option is an integer define.

DEFAULT VALUE:

The default value is 0.

DESCRIPTION:

The value of this configuration option defines the maximum number of Classic API Tasks that can be concurrently active.

NOTES:

This object class can be configured in unlimited allocation mode, see Unlimited Objects.

The calculations for the required memory in the RTEMS Workspace for tasks assume that each task has a minimum stack size and has floating point support enabled. The configuration option CONFIGURE_EXTRA_TASK_STACKS is used to specify task stack requirements above the minimum size required.

A future enhancement to <rtems/confdefs.h> could be to eliminate the assumption that all tasks have floating point enabled. This would require the addition of a new configuration parameter to specify the number of tasks which enable floating point support.

CONSTRAINTS:

The following constraints apply to this configuration option:

• The value of the configuration option shall be greater than or equal to zero.

• The value of the configuration option shall be less than or equal to 65535.

• The value of the configuration option shall be less than or equal to a BSP-specific and application-specific value which depends on the size of the memory available to the application.

• The value of the configuration option shall be small enough so that the task stack space calculation carried out by <rtems/confdefs.h> does not overflow an integer of type uintptr_t.

• The value of the configuration option may be defined through rtems_resource_unlimited() the enable unlimited objects for the object class, if the value passed to rtems_resource_unlimited() satisfies all other constraints of the configuration option.

## 26.9.9. CONFIGURE_MAXIMUM_TIMERS¶

CONSTANT:

CONFIGURE_MAXIMUM_TIMERS

OPTION TYPE:

This configuration option is an integer define.

DEFAULT VALUE:

The default value is 0.

DESCRIPTION:

The value of this configuration option defines the maximum number of Classic API Timers that can be concurrently active.

NOTES:

This object class can be configured in unlimited allocation mode, see Unlimited Objects.

CONSTRAINTS:

The following constraints apply to this configuration option:

• The value of the configuration option shall be greater than or equal to zero.

• The value of the configuration option shall be less than or equal to 65535.

• The value of the configuration option shall be less than or equal to a BSP-specific and application-specific value which depends on the size of the memory available to the application.

• The value of the configuration option may be defined through rtems_resource_unlimited() the enable unlimited objects for the object class, if the value passed to rtems_resource_unlimited() satisfies all other constraints of the configuration option.

## 26.9.10. CONFIGURE_MAXIMUM_USER_EXTENSIONS¶

CONSTANT:

CONFIGURE_MAXIMUM_USER_EXTENSIONS

OPTION TYPE:

This configuration option is an integer define.

DEFAULT VALUE:

The default value is 0.

DESCRIPTION:

The value of this configuration option defines the maximum number of Classic API User Extensions that can be concurrently active.

NOTES:

This object class cannot be configured in unlimited allocation mode.

CONSTRAINTS:

The following constraints apply to this configuration option:

• The value of the configuration option shall be greater than or equal to zero.

• The value of the configuration option shall be less than or equal to 65535.

• The value of the configuration option shall be less than or equal to a BSP-specific and application-specific value which depends on the size of the memory available to the application.

CONSTANT:

CONFIGURE_MINIMUM_TASKS_WITH_USER_PROVIDED_STORAGE

OPTION TYPE:

This configuration option is an integer define.

DEFAULT VALUE:

The default value is 0.

DESCRIPTION:

The value of this configuration option defines the minimum count of Classic API Tasks which are constructed by rtems_task_construct().

NOTES:

By default, the calculation for the required memory in the RTEMS Workspace for tasks assumes that all Classic API Tasks are created by rtems_task_create(). This configuration option can be used to reduce the required memory for the system-provided task storage areas since tasks constructed by rtems_task_construct() use a user-provided task storage area.

CONSTRAINTS:

The following constraints apply to this configuration option:

• The value of the configuration option shall be greater than or equal to zero.

• The value of the configuration option shall be less than or equal to CONFIGURE_MAXIMUM_TASKS.