W78E516DPG Nuvoton Technology Corporation of America, W78E516DPG Datasheet - Page 61

• Manufacturer Part Number: W78E516DPG
• Description: IC MCU 8-BIT 64K FLASH 44-PLCC
• Manufacturer: Nuvoton Technology Corporation of America
• Series: W78r

Specifications of W78E516DPG

• Core Processor: 8052
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: EBI/EMI, UART/USART
• Peripherals: POR, WDT
• Number Of I /o: 36
• Program Memory Size: 64KB (64K x 8)
• Program Memory Type: FLASH
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Oscillator Type: External
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 44-PLCC
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -

the divide by 16 counters.
The 16 states of the counter effectively divide the bit time into 16 slices. The bit detection is done on a
best of three basie. The bit detector samples the RxD pin, at the 8th, 9th and 10th counter states. By
using a majority 2 of 3 voting system, the bit value is selected. This is done to improve the noise
rejection feature of the serial port. If the first bit detected after the falling edge of RxD pin is not 0, then
this indicates an invalid start bit, and the reception is immediately aborted. The serial port again looks
for a falling edge in the RxD line. If a valid start bit is detected, then the rest of the bits are also
detected and shifted into the SBUF.
After shifting in 8 data bits, there is one more shift to do, after which the SBUF and RB8 are loaded
and RI is set. However certain conditions must be met before the loading and setting of RI can be
done.
If these conditions are met, then the stop bit goes to RB8, the 8 data bits go into SBUF and RI is set.
Otherwise the received frame may be lost. After the middle of the stop bit, the receiver goes back to
looking for a 1-to-0 transition on the RxD pin.
16.3 MODE 2
This mode uses a total of 11 bits in asynchronous full-duplex communication. The functional
SMOD
Overflow
Timer 1
TCLK
RCLK
1/2
1. RI must be 0 and
2. Either SM2 = 0, or the received stop bit = 1.
0
0
0
1
SAMPLE
RXD
Overflow
Timer 2
1
1
DETECTOR
1-To-0
1/16
Preliminary W78E516D/ W78E058D Data Sheet
1/16
Figure 16- 2 Serial port mode 1
RX CLOCK
TX START
TX CLOCK
TX START
Write to
SBUF
DETECTOR
BIT
Controllor
Serial
- 61 -
LOAD SBUF
Data Bus
Internal
RX SHIFT
TX SHIFT
TI
RI
Receive Shift Register
1
0
CLOCK
Transmit Shift Register
SIN
Publication Release Date: July 30, 2008
STOP
START
PARIN
CLOCK
LOAD
PAROUT
D8
SOUT
Serial Interrupt
SBUF
RB8
TXD
Revision A01
Read SBUF
Data Bus
Internal