at91rm3400 ATMEL Corporation, at91rm3400 Datasheet - Page 59

• Manufacturer Part Number: at91rm3400
• Description: Atmel Advanced At91 Arm Microcontroller
• Manufacturer: ATMEL Corporation

Embedded Software Services
Definition
ROM Entry Service
Table 18. Initialization of the ROM Entry Service and Use with an Open Service Method
1790A–ATARM–11/03
Application Memory Space
// Init the ROM Entry Service
AT91S_RomBoot const *pAT91;
pAT91 = AT91C_ROM_BOOT_ADDRESS;
// Allocation of the service structure
AT91S_CtlTempo tempo;
// Call the Service Open method
pAT91->OpenCtlTempo(&tempo, ...);
// Use of tempo methods
tempo.CtlTempoCreate(&tempo, ...);
Several AT91 products embed ROM. In most cases, the ROM integrates a bootloader and
several services that may speed up the application and reduce the application code size.
When software is fixed in the ROM, the address of each object (function, constant, table, etc.)
must be related to a customer application. This is done by providing an address table to the
linker. For each version of ROM, a new address table must be provided and all client applica-
tions must be recompiled.
The Embedded Software Services offer another solution to access objects stored in ROM. For
each embedded service, the customer application requires only the address of the Service
Entry Point (see Section ).
Even if these services have only one entry point (
be specified to the linker. The Embedded Software Services solve this problem by providing a
dedicated service: the ROM Entry Service.
The goal of this product-dedicated service is to provide just one address to access all ROM
functionalities.
The ROM Entry Service of a product is a structure named
of this structure point to the open functions of all services stored in ROM (function
AT91F_Open_<Service>
AT91S_RomBoot
The application obtains the address of the ROM Entry Service and initializes an instance of
the
ROM, the application uses the appropriate member of the
The address of the
exception vectors.
AT91S_RomBoot
has to be published.
structure. To obtain the Open Service Method of another service stored in
AT91S_RomBoot
) but also the CRC and Sine Arrays. Thus, only the address of the
ROM Memory Space
AT91S_TempoStatus AT91F_OpenCtlTempo(
{
...
}
AT91S_TempoStatus AT91F_CtlTempoCreate (
{
...
}
can be found at the beginning of the ROM, after the
AT91PS_CtlTempo pCtlTempo,
void const *pTempoTimer )
AT91PS_CtlTempo pCtrl,
AT91PS_SvcTempo pTempo)
AT91F_Open_<Service>
AT91S_RomBoot
AT91S_RomBoot
AT91RM3400
function), they must
structure.
. Some members
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