UPD78F0138 NEC, UPD78F0138 Datasheet - Page 311

• Manufacturer Part Number: UPD78F0138
• Description: (UPD78xxxx) 8-Bit Single-Chip Microcontrollers
• Manufacturer: NEC

(2) Communication operation
(a) Format and waveform example of normal transmit/receive data
Figures 14-13 and 14-14 show the format and waveform example of the normal transmit/receive data.
1. LSB-first transmission/reception
2. MSB-first transmission/reception
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
Start
Start
bit
bit
X
D6 pin outputs normal or inverted data is specified by bit 0 (TXDLV6) of ASICL6.
Figure 14-13. Format of Normal UART Transmit/Receive Data
D0
D7
D1
D6
CHAPTER 14 SERIAL INTERFACE UART6
D2
D5
User’s Manual U16228EJ2V0UD
D3
D4
Character bits
Character bits
1 data frame
1 data frame
D4
D3
D5
D2
D6
D1
D7
D0
Parity
Parity
bit
bit
Stop bit
Stop bit
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