Service Layer Overview - Texas Instruments TMS320C6000 Reference Manual

1.3 Service Layer Overview

Figure 1–2. API Modules within Service Layer
The service layer is where the actual APIs are defined and is the layer the user
interfaces to. It is possible for the user to interface directly into the HAL but this
is not advisable because it could have undesired side effects on the operation
of the service layer APIs. For example, you would not want to use the HAL to
directly write to a DMA register while that register is in use by the DMA service
layer API. If however, the user decides not to use the service layer at all, the
HAL is available and can still save the user time and effort.
Figure 1–2 illustrates the individual API modules within the service layer. This
architecture allows for future expansion of the CSL because new API modules
can be added to the service layer as new peripheral devices emerge.
CACHE CSL DAT
It is important to note that not all devices support all API modules. This de-
pends on if the device actually has the peripheral that an API covers. For ex-
ample, the EDMA API module is not supported on a 'C6201 because this de-
vice does not have an EDMA peripheral. Other modules, however, are sup-
ported on all devices such as the IRQ module. As will be shown later in the API
Reference section, each module has a compile time constant symbol defined
that denotes if the module is supported or not for a given device. For example,
the symbol EDMA_SUPPORT has a value of 1 if the current device supports it,
and a value of 0 otherwise. You can use these support symbols in their applica-
tion code to make decisions if so desired.
Note:
When using the CSL, it is up to the user to define a project-wide symbol from
a predetermined set to identify which device is being used. This device iden-
tification symbol is then used in the CSL header files to conditionally define
the support symbols. See the CHIP API reference (section 4.5, CHIP , on
page 4-19) for more information.
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CHIP DMA
Service Layer Overview
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STDINC TIMER
Introduction 1-5