tmp88ps42ng TOSHIBA Semiconductor CORPORATION, tmp88ps42ng Datasheet - Page 178

• Manufacturer Part Number: tmp88ps42ng
• Description: 8 Bit Microcontroller Tlcs-870/x Series
• Manufacturer: TOSHIBA Semiconductor CORPORATION

14. Asynchronous Serial interface (UART)
14.6 STOP Bit Length
14.6 STOP Bit Length
14.7 Parity
14.8 Transmit/Receive Operation
14.8.1 Data Transmit Operation
14.8.2 Data Receive Operation
Select a transmit stop bit length (1 bit or 2 bits) by UARTCRA<STBT>.
Set parity / no parity by UARTCRA<PE> and set parity type (Odd- or Even-numbered) by UARTCRA<EVEN>.
(Transmit data buffer). Writing data in TDBUF zero-clears UARTSR<TBEP>, transfers the data to the trans-
mit shift register and the data are sequentially output from the TXD pin. The data output include a one-bit start
bit, stop bits whose number is specified in UARTCRA<STBT> and a parity bit if parity addition is specified.
Select the data transfer baud rate using UARTCRA<BRG>. When data transmit starts, transmit buffer empty
flag UARTSR<TBEP> is set to “1” and an INTTXD interrupt is generated.
written to TDBUF, the TXD pin is fixed at high level. When transmitting data, first read UARTSR, then write
data in TDBUF. Otherwise, UARTSR<TBEP> is not zero-cleared and transmit does not start.
RDBUF (Receive data buffer). At this time, the data transmitted includes a start bit and stop bit(s) and a parity
bit if parity addition is specified. When stop bit(s) are received, data only are extracted and transferred to
RDBUF (Receive data buffer). Then the receive buffer full flag UARTSR<RBFL> is set and an INTRXD
interrupt is generated. Select the data transfer baud rate using UARTCRA<BRG>.
data buffer) but discarded; data in the RDBUF are not affected.
Set UARTCRA<TXE> to “1”. Read UARTSR to check UARTSR<TBEP> = “1”, then write data in TDBUF
While UARTCRA<TXE> = “0” and from when “1” is written to UARTCRA<TXE> to when send data are
Set UARTCRA<RXE> to “1”. When data are received via the RXD pin, the receive data are transferred to
If an overrun error (OERR) occurs when data are received, the data are not transferred to RDBUF (Receive
Note:When a receive operation is disabled by setting UARTCRA<RXE> bit to “0”, the setting becomes valid when
data receive is completed. However, if a framing error occurs in data receive, the receive-disabling setting
may not become valid. If a framing error occurs, be sure to perform a re-receive operation.
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TMP88PS42NG