W90N740CDG Nuvoton Technology Corporation of America, W90N740CDG Datasheet - Page 142

• Manufacturer Part Number: W90N740CDG
• Description: IC MCU ARM7 TDMI 176-LQFP
• Manufacturer: Nuvoton Technology Corporation of America
• Series: W90r

Specifications of W90N740CDG

• Core Processor: ARM7
• Core Size: 16/32-Bit
• Speed: 80MHz
• Connectivity: EBI/EMI, Ethernet, UART/USART, USB
• Peripherals: DMA, POR, WDT
• Number Of I /o: 21
• Program Memory Type: ROMless
• Ram Size: 10K x 8
• Voltage - Supply (vcc/vdd): 1.62 V ~ 3.6 V
• Oscillator Type: External
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 176-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Program Memory Size: -
• Data Converters: -

7.9
The Universal Asynchronous Receiver/Transmitter (UART) performs a serial-to-parallel conversion
on data characters received from the peripheral such as MODEM, and a parallel-to-serial conversion on
data characters received from the CPU.
There are five types of interrupts, i.e., line status interrupt, transmitter FIFO empty interrupt, receiver
threshold level reaching interrupt, time out interrupt, and MODEM status interrupt. One 16-byte
transmitter FIFO (TX_FIFO) and one 16-byte (plus 3-bit of error data per byte) receiver FIFO (RX_FIFO)
has been built in to reduce the number of interrupts presented to the CPU. The CPU can completely read
the status of the UART at any time during the operation. The reported status information includes the
type and condition of the transfer operations being performed by the UART, as well as any error
conditions (parity, overrun, framing, or break interrupt) found. The UART includes a programmable baud
rate generator that is capable of dividing crystal clock input by divisors to produce the clock that
transmitter and receiver needed. The equation is
The Features of the UART:
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UART Controller
Transmitter and receiver are buffered with a 16-byte FIFO each to reduce the number of
interrupts.
Full set of MODEM control functions (CTS, RTS, DSR, DTR, RI and DCD)
Fully programmable serial-interface characteristics:
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Break generation and detection
False start bit detection
Parity, overrun, and framing error detection
Full prioritized interrupt system controls
5-, 6-, 7-, or 8-bit character
Even, odd, or no-parity bit generation and detection
1-, 1&1/2, or 2-stop bit generation
Baud rate generation
BaudOut = crystal clock / 16 * [Divisor + 2].
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W90N740CD/W90N740CDG
Publication Release Date: Aug. 18, 2005
Revision A6