NEC 78K0 Series User Manual page 365

(2) Communication operation
(a) Format and waveform example of normal transmit/receive data
Figures 15-13 and 15-14 show the format and waveform example of the normal transmit/receive data.
Figure 15-13. Format of Normal UART Transmit/Receive Data
1. LSB-first transmission/reception
Start
bit
2. MSB-first transmission/reception
Start
bit
One data frame consists of the following bits.
• Start bit ... 1 bit
• Character bits ... 7 or 8 bits
• Parity bit ... Even parity, odd parity, 0 parity, or no parity
• Stop bit ... 1 or 2 bits
The character bit length, parity, and stop bit length in one data frame are specified by asynchronous serial
interface operation mode register 6 (ASIM6).
Whether data is communicated with the LSB or MSB first is specified by bit 1 (DIR6) of asynchronous serial
interface control register 6 (ASICL6).
Whether the T D6 pin outputs normal or inverted data is specified by bit 0 (TXDLV6) of ASICL6.
X
CHAPTER 15 SERIAL INTERFACE UART6
1 data frame
D0 D1 D2 D3 D4
Character bits
1 data frame
D7 D6 D5 D4 D3
Character bits
Preliminary User's Manual U17260EJ3V1UD
Parity
D5 D6 D7
bit
Parity
D2 D1 D0
bit
Stop bit
Stop bit
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