ADSP-BF535 Blackfin Processor Hardware Reference
11-7
Serial Port Controllers
ferred, the SPORT generates the transmit interrupt. The
SPORTx_TX
register is then available for the next data word, even though the transmis-
sion of the first word continues.
As a SPORT receives bits, they accumulate in an internal receive register.
When a complete word has been received, it is written to the
SPORTx_RX
register and the receive interrupt for that SPORT is generated. Interrupts
are generated differently if DMA block transfers are performed. For infor-
mation about DMA, see
“Direct Memory Access” on page 9-1
.
SPORT Disable
The SPORTs are automatically disabled by a hardware or software reset. A
SPORT can also be disabled directly by clearing the SPORT’s transmit or
receive enable bits (
TSPEN
in the
SPORTx_TX_CONFIG
control register and
RSPEN
in the
SPORTx_RX_CONFIG
control register, respectively). Each
method has a different effect on the SPORT.
A reset disables the SPORTs by clearing the
SPORTx_TX_CONFIG
and
SPORTx_RX_CONFIG
control registers (including the
TSPEN
and
RSPEN
enable
bits) and the
TSCLKDIVx
,
RSCLKDIVx
,
SPORTx_TFSDIVx
, and
SPORTx_RFSDIVx
clock and frame sync divisor registers. Any ongoing operations are
aborted.
Disabling the
TSPEN
and
RSPEN
enable bits disables the SPORTs and
aborts any ongoing operations. Status bits are also cleared. Configuration
bits remain unaffected and can be read by the software in order to be
altered or overwritten. To disable the SPORT output clock after the
SPORT has been enabled, set the SPORT to receive an external clock.
The SPORTs are ready to start transmitting or receiving data three serial
clock cycles after they are enabled in the
SPORTx_TX_CONFIG
or
SPORTx_RX_CONFIG
control register. No serial clock cycles are lost from this
point on.
Summary of Contents for ADSP-BF535 Blackfin
Page 80: ...Development Tools 1 26 ADSP BF535 Blackfin Processor Hardware Reference...
Page 312: ...Working With Memory 6 86 ADSP BF535 Blackfin Processor Hardware Reference...
Page 332: ...System Interfaces 7 20 ADSP BF535 Blackfin Processor Hardware Reference...
Page 360: ...Dynamic Power Management Controller 8 28 ADSP BF535 Blackfin Processor Hardware Reference...
Page 446: ...Beginning and Ending an SPI Transfer 10 40 ADSP BF535 Blackfin Processor Hardware Reference...
Page 522: ...Timing Examples 11 76 ADSP BF535 Blackfin Processor Hardware Reference...
Page 562: ...IrDA Support 12 40 ADSP BF535 Blackfin Processor Hardware Reference...
Page 608: ...PCI I O Issues 13 46 ADSP BF535 Blackfin Processor Hardware Reference...
Page 672: ...References 14 64 ADSP BF535 Blackfin Processor Hardware Reference...
Page 810: ...SDRAM Controller SDC 18 86 ADSP BF535 Blackfin Processor Hardware Reference...
Page 811: ...ADSP BF535 Blackfin Processor Hardware Reference 18 87 External Bus Interface Unit...
Page 812: ...SDRAM Controller SDC 18 88 ADSP BF535 Blackfin Processor Hardware Reference...
Page 860: ...DMA Bus Debug Registers 20 30 ADSP BF535 Blackfin Processor Hardware Reference...