AT91M55800A Datasheet, PDF (135/227 Pages) ATMEL Corporation – ARM Thumb Microcontrollers

USART User Interface
Base Address USART0:
Base Address USART1:
Base Address USART2:
0xFFFC0000 (Code Label USART0_BASE)
0xFFFC4000 (Code Label USART1_BASE)
0xFFFC8000 (Code Label USART2_BASE)
Table 17. USART Memory Map
Offset
Register
Name
0x00
Control Register
US_CR
0x04
Mode Register
US_MR
0x08
Interrupt Enable Register
US_IER
0x0C
Interrupt Disable Register
US_IDR
0x10
Interrupt Mask Register
US_IMR
0x14
Channel Status Register
US_CSR
0x18
Receiver Holding Register
US_RHR
0x1C
Transmitter Holding Register
US_THR
0x20
Baud Rate Generator Register
US_BRGR
0x24
Receiver Time-out Register
US_RTOR
0x28
Transmitter Time-guard Register
US_TTGR
0x2C
Reserved
–
0x30
Receive Pointer Register
US_RPR
0x34
Receive Counter Register
US_RCR
0x38
Transmit Pointer Register
US_TPR
0x3C
Transmit Counter Register
US_TCR
AT91M55800A
Access
Write-only
Read/write
Write-only
Write-only
Read-only
Read-only
Read-only
Write-only
Read/write
Read/write
Read/write
–
Read/write
Read/write
Read/write
Read/Write
Reset State
–
0
–
–
0
0x18
0
–
0
0
0
–
0
0
0
0
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