
ADSP-21462/ADSP-21465/ADSP-21467/ADSP-21469
Preliminary Technical Data
Universal Asynchronous Receiver-Transmitter
(UART) Port—Receive and Transmit Timing
Figure 36 describes UART port receive and transmit operations.
The maximum baud rate is PCLK/16 where PCLK = 1/tPCLK.
As shown in Figure 36 there is some latency between the gener-
Table 45. UART Port
ation of internal UART interrupts and the external data
operations. These latencies are negligible at the data transmis-
sion rates for the UART.
Parameter
Min
Max
Unit
Timing Requirement
t RXD 1
Incoming Data Pulse Width
TBD
TBD
ns
Switching Characteristic
TBD
TBD
1
t TXD 1 Outgoing Data Pulse Width
UART signals RXD and TXD are routed through DPI P14-1 pins using the SRU.
DPI_P14 - 1
DATA(5 - 8 )
[RXD]
TBD
TBD
ns
S TOP
RECEIVE
INTERNAL
UART RECEIVE
INTERRUPT
S TART
tRXD
UART RECEIVE BIT S ET BY DATA S TOP;
CLEARED BY FIFO READ
DPI_P14 - 1
[TXD]
DATA(5 - 8 )
S TOP(1 - 2)
TRAN S MIT
INTERNAL
UART TRAN S MIT
INTERRUPT
tTXD
Figure 36. UART Port—Receive and Transmit Timing
UART TRAN S MIT BIT S ET BY PROGRAM;
CLEARED BY WRITE TO TRAN S MIT
Rev. PrC
| Page 48 of 62 | January 2009