UARTx Control and Status Registers
12-10
ADSP-BF535 Blackfin Processor Hardware Reference
Because of the destructive nature of these read operations, special care
should be taken. See
“Speculative Load Execution” on page 6-81
and
“Conditional Load Behavior” on page 6-82
for more information.
UARTx Divisor Latch Registers (UARTx_DLL,
UARTx_DLH)
The bit rate is characterized by the system clock (
SCLK
) and the 16-bit
Divisor. The Divisor is split into the Divisor Latch Low Byte register
(
UARTx
_
DLL
) and the Divisor Latch High Byte register (
UARTx_DLH
), as
shown in
Figure 12-8
. These registers form a 16-bit divisor. The baud
clock is divided by 16 so that:
BAUD RATE = SCLK/(16
Divisor)
Divisor = 65,536
when
UARTx_DLL
=
UARTx_DLH = 0
Figure 12-7. UARTx Interrupt Identification Registers
Table 12-6. UARTx Interrupt Identification Register MMR Assignments
Register Name
Memory-Mapped Address
UART0_IIR
0xFFC0 1804
UART1_IIR
0xFFC0 1C04
0
0
0
0
0
NINT (Pending interrupt)
7
6
5
4
3
2
1
0
1
0
Reset = 0x01
0
UARTx Interrupt Identification Registers (UARTx_IIR)
RO
STATUS[1:0]
0 - Interrupt pending
1 - No interrupt pending
00 - Modem status interrupt. Read UARTx_MSR to clear.
01 - UARTx_THR empty. Write UARTx_THR or read
UARTx_IIR to clear.
10 - Receive data ready. Read UARTx RBR to clear.
11 - Receive line status. Read UARTx_LSR to clear.
For MMR assignments,
see
Table 12-6
.
Содержание ADSP-BF535 Blackfin
Страница 80: ...Development Tools 1 26 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 312: ...Working With Memory 6 86 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 332: ...System Interfaces 7 20 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 360: ...Dynamic Power Management Controller 8 28 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 446: ...Beginning and Ending an SPI Transfer 10 40 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 522: ...Timing Examples 11 76 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 562: ...IrDA Support 12 40 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 608: ...PCI I O Issues 13 46 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 672: ...References 14 64 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 810: ...SDRAM Controller SDC 18 86 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 811: ...ADSP BF535 Blackfin Processor Hardware Reference 18 87 External Bus Interface Unit...
Страница 812: ...SDRAM Controller SDC 18 88 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 860: ...DMA Bus Debug Registers 20 30 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 908: ...SDRAM Controller External Bus Interface Unit B 36 ADSP BF535 Blackfin Processor Hardware Reference...