UART controller data flow

AN3123

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Doc ID 16862 Rev 2

6

UART controller data flow

Figure 1.

UART controller data flow

Figure 1 illustrates how data flows from user space down to the hardware interfaces and

flows back up.

The reading and writing processes use the HAL functions which are exposed to the user.

Then the corresponding APIs of the UART hardware layer are called for the transmission

and reception of data. The direction of transmission and reception are as shown in Figure 1.

6.1

UART data registers

SPEAr300

Base Address for UART: 0xD0000000

SPEAr600

Base Address for UART1: 0xD0000000

Base Address for UART2: 0xD0080000

Offset Value: ‘h000

UART hardware (ARM Primecell PL011)

UART hardware abstraction layer (HAL)

User exposed layer

User applications

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