UART Registers
13-28
ADSP-BF537 Blackfin Processor Hardware Reference
The UART’s DMA is enabled by first setting up the system DMA control
registers and then enabling the UART
ERBFI
and/or
ETBEI
interrupts in
the
UARTx_IER
register. This is because the interrupt request lines double
as DMA request lines. Depending on whether DMA is enabled or not,
upon receiving these requests, the DMA control unit either generates a
direct memory access or passes the UART interrupt on to the system inter-
rupt handling unit. However, UART’s error interrupt goes directly to the
system interrupt handling unit, bypassing the DMA unit completely.
The
ELSI
bit enables interrupt generation on an independent interrupt
channel when any of the following conditions are raised by the respective
bit in the
UARTx_LSR
register:
• Receive overrun error (
OE
)
• Receive parity error (
PE
)
• Receive framing error (
FE
)
• Break interrupt (
BI
)
Figure 13-12. UART Interrupt Enable Registers
15 14
13 12
11 10
9
8
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
ERBFI (Enable Receive
Buffer Full Interrupt)
UART Interrupt Enable Registers (UARTx_IER)
ETBEI (Enable Transmit
Buffer Empty Interrupt)
ELSI (Enable RX Status Interrupt)
0 - No interrupt
1 - Generate RX interrupt if
DR bit in UARTx_LSR is
set
0 - No interrupt
1 - Generate TX interrupt if
THRE bit in UARTx_LSR is
set
0 - No interrupt
1 - Generate line status interrupt if
any of UARTx_LSR[4:1] is set
Reset = 0x0000
UART0:
0xFFC0 0404
UART1:
0xFFC0 2004
Summary of Contents for Blackfin ADSP-BF537
Page 42: ...Contents xlii ADSP BF537 Blackfin Processor Hardware Reference ...
Page 90: ...Development Tools 1 32 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 138: ...Programming Examples 4 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 340: ...SDC Programming Examples 6 84 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 606: ...Programming Examples 9 94 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 660: ...Programming Examples 10 54 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 720: ...Electrical Specifications 11 60 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 840: ...Programming Examples 13 42 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 876: ...Programming Examples 14 36 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 938: ...Programming Examples 15 62 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 958: ...Programming Examples 17 12 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 986: ...Programming Examples 18 28 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1162: ...G 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1218: ...Index I 56 ADSP BF537 Blackfin Processor Hardware Reference ...