ADSP-BF537 Blackfin Processor Hardware Reference
13-15
UART Port Controllers
For example, predefine ASCII character “@” (0x40) as the autobaud
detection character and measure the period between two subsequent fall-
ing edges. As shown in
, measure the period between the
falling edge of the start bit and the falling edge after bit 6. Since this
period encloses 8 bits, apply the formula:
DIVISOR = TIMERx_PERIOD >> 7
An example is provided in
.
Programming Model
The following sections describe a programming model for the UARTs.
Non-DMA Mode
In non-DMA mode, data is moved to and from the UART by the proces-
sor core. To transmit a character, load it into
UARTx_THR
. Received data
can be read from
UARTx_RBR
. The processor must write and read one char-
acter at time.
To prevent any loss of data and misalignments of the serial datastream, the
UARTx_LSR
register provides two status flags for handshaking—
THRE
and
DR
.
Figure 13-6. Autobaud Detection Character 0x40
PERIOD
STOP
S
1
2
3
4
5
6
7
0
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 ...