AT89C5132 Atmel Corporation, AT89C5132 Datasheet - Page 110

• Manufacturer Part Number: AT89C5132
• Manufacturer: Atmel Corporation

Specifications of AT89C5132

• Flash (kbytes): 64 Kbytes
• Max. Operating Frequency: 20 MHz
• Cpu: 8051-12C
• Max I/o Pins: 44
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 1
• Uart: 1
• Adc Channels: 2
• Adc Resolution (bits): 10
• Adc Speed (ksps): 22.7
• Sram (kbytes): 2.25
• Self Program Memory: API
• Operating Voltage (vcc): 2.7 to 3.6
• Timers: 2
• Isp: UART/USB
• Watchdog: Yes

18.3.3
110
AT89C5132
Baud Rate Selection
(Mode 0)
Figure 18-5. Reception Waveforms (Mode 0)
In mode 0, the baud rate can be either fixed or variable.
As shown in Figure 18-6, the selection is done using M0SRC bit in BDRCON register.
Figure 18-7 gives the baud rate calculation formulas for each baud rate source.
Figure 18-6. Baud Rate Source Selection (mode 0)
Figure 18-7. Baud Rate Formulas (Mode 0)
Write to SCON
a. Fixed Formula
Baud_Rate
RXD
TXD
RI
CLOCK
CLOCK
IBRG0
PER
=
F
PER
6
Set REN, Clear RI
D0
÷ 6
D1
D2
BDRCON.0
M0SRC
D3
0
1
D4
BRL= 256
Baud_Rate=
D5
To
Serial Port
b. Variable Formula
-
D6
6
(1-SPD)
6
(1-SPD)
D7
⋅
16
⋅
F
16
PER
⋅
F
Baud_Rate
PER
⋅
4173E–USB–09/07
(256 -BRL)