XE8805 Datasheet, PDF (75/156 Pages) Semtech Corporation – Data Acquisition MCU

XE8805/05A
14.1 Features
• Full duplex operation with buffered receiver and transmitter.
• Internal baud rate generator with 12 programmable baud rates (300 - 115200).
• 7 or 8 bits word length.
• Even, odd, or no-parity bit generation and detection
• 1 stop bit
• Error receive detection: Start, Parity, Frame and Overrun
• Receiver echo mode
• 2 interrupts (receive full and transmit empty)
• Enable receive and/or transmit
• Invert pad Rx and/or Tx
14.2 Overview
The UART pins are PB[7], which is used as Rx - receive and PB[6] as Tx - transmit.
14.3 Registers map
pos. RegUartCmd rw
7
SelXtal
rw
6
UartEnRx2
rw
5-3 UartRcSel(2:0) rw
2
UartPM
rw
1
UartPE
rw
0
UartWL
rw
Reset
0 resetsystem
0 resetsystem
000 resetsystem
0 resetsystem
0 resetsystem
1 resetsystem
Description
Select input clock: 0 = RC, 1 = xtal
Enable Uart Reception
RC prescaler selection
Select parity mode: 0 = odd, 1 = even
Enable parity: 1 = with parity, 0 = no parity
Select word length: 1 = 8 bits, 0 = 7 bits
Table 14-1: RegUartCmd
Pos. RegUartCtrl rw
7
UartEcho
rw
reset
0 resetsystem
6
UartEnRx1
rw
0 resetsystem
5
UartEnTx
rw
0 resetsystem
4
UartXRx
rw
0 resetsystem
3
UartXTx
rw
0 resetsystem
2-0 UartBR(2:0) rw 101 resetsystem
Description
Enable echo mode:
1 = echo Rx->Tx, 0 = no echo
Enable uart reception
Enable uart transmission
Invert pad Rx
Invert pad Tx
Select baud rate
Table 14-2: RegUartCtrl
pos. RegUartTx rw
7-0
UartTx
rw
reset
00000000
resetsystem
Table 14-3: RegUartTx
Description
Data to be sent
© Semtech 2006
14-2
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