W77E058A40DL Nuvoton Technology Corporation of America, W77E058A40DL Datasheet - Page 63

• Manufacturer Part Number: W77E058A40DL
• Description: IC MCU 8-BIT 32K FLASH 40-DIP
• Manufacturer: Nuvoton Technology Corporation of America
• Series: W77r

Specifications of W77E058A40DL

• Program Memory Type: FLASH
• Program Memory Size: 32KB (32K x 8)
• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: EBI/EMI, Serial Port
• Peripherals: POR, WDT
• Number Of I /o: 32
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 40-DIP
• Cpu Family: W77
• Device Core: 8051
• Device Core Size: 8b
• Frequency (max): 40MHz
• Interface Type: UART
• Total Internal Ram Size: 1KB
• # I/os (max): 32
• Number Of Timers - General Purpose: 3
• Operating Supply Voltage (typ): 5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 4.5V
• Instruction Set Architecture: CISC
• Operating Temp Range: 0C to 70C
• Operating Temperature Classification: Commercial
• Mounting: Through Hole
• Pin Count: 40
• Package Type: PDIP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Lead Free Status / RoHS Status: Compliant, Lead free / RoHS Compliant

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 9 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.
(SMOD_1)
SMOD=
div. by 4
div. by 64
div. by 1024 osc/512
Mode
1. RI must be 0 and
2. Either SM2 = 0, or the received stop bit = 1.
Clock Source
SAMPLE
RXD
2
0
osc/2
osc/32
input
1
DETECTOR
1-TO-0
16
16
Write to
SBUF
RX CLOCK
RX START
TX START
TX CLOCK
CONTROLLER
DETECTOR
SERIAL
Figure 22. Serial Port Mode 2
BIT
Data Bus
Internal
RX SHIFT
SHIFT
LOAD
SBUF
TX
TB8
RI
TI
- 63 -
CLOCK
SIN
Receive Shift Register
PAROUT
Publication Release Date: February 17, 2005
START
LOAD
CLOCK
STOP
D8
PARIN
Transmit Shift Register
D8
SOUT
SBUF
RB8
Serial Port
Interrupt
Read
SBUF
TXD
W77E58
Internal
Revision A6
Data
Bus