UPD784938 Datasheet, PDF (427/733 Pages) NEC – 16-Bit Single-Chip Microcontrollers

CHAPTER 18 ASYNCHRONOUS SERIAL INTERFACE/3-WIRE SERIAL I/O
The µPD784938 incorporates two serial interface channels for which asynchronous serial interface (UART) mode or
3-wire serial I/O (IOE) mode can be selected.
The two UART/IOE channels have completely identical functions. In this chapter, therefore, unless stated otherwise,
UART/IOE1 will be described as representative of both UART/IOEs. When used as UART2/IOE2, the UART/IOE1 register
names, bit names and pin names should be read as their UART2/IOE2 equivalents as shown in Table 18-1.
Table 18-1. Differences between UART/IOE1 and UART2/IOE2 Names
Pin names
Item
Asynchronous serial interface mode register
Asynchronous serial interface mode register bit names
Asynchronous serial interface status register
Asynchronous serial interface status register bit names
Clocked serial interface mode register
Clocked serial interface mode register bit names
Baud rate generator control register
Baud rate generator control register bit names
Interrupt request names
UART/IOE1
P25/ASCK/SCK1, P30/RxD/SI1,
P31/TxD/SO2
ASIM
TXE, RXE, PS1, PS0, CL, SL,
ISRM, SCK
ASIS
PE, FE, OVE
CSIM1
CTXE1, CRXE1, DIR1, CSCK1
BRGC
TPS0 to TPS3, MDL0 to MDL3
INTSR/ITCSI1, INTSER, INTST
Interrupt control registers and bit names used in this
chapter
SRIC, CSIIC1, SERIC, STIC,
SRIF, CSIIF1, SERIF, STIF
UART2/IOE2
P12/ASCK2/SCK2, P13/RxD2/SI2,
P14/TxD2/SO2
ASIM2
TXE2, RXE2, PS21, PS20, CL2,
SL2, ISRM2, SCK2
ASIS2
PE2, FE2, OVE2
CSIM2
CTXE2, CRXE2, DIR2, CSCK2
BRGC2
TPS20 to TPS23, MDL20 to MDL23
INTSR2/INTCSI2, INTSER2,
INTST2
SRIC2, CSIIC2, SERIC2, STIC2,
SRIF2, SCIIF2, SERIF2, STIF2
Preliminary User’s Manual U13987EJ1V0UM00
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