Renesas M32R/ECU Series User Manual page 532

12
Table 12.6.1 Transfer Data in UART Mode
Bit Name
ST (start bit)
Bits 0–8 (character bits)
PAR (parity bit)
SP (stop bit)
b0
Notes: • The high-order bits of the selected character length in the SIO Receive Buffer Register are fixed to "0".
Figure 12.6.2 Selectable Data Formats during UART Mode
Content
Indicates the beginning of data transmission. This is a low-level signal of a one bit
period, which is added immediately preceding the transmit data.
Transmit/receive data transferred via serial I/O. In UART mode, 7, 8 or 9 bits of data
can be transmitted/received.
Added to the transmit/receive character. When parity is enabled, parity is
automatically set in such a way that the number of 1's in the character including the
parity bit itself is always even or odd as selected by the even/odd parity select bit.
Indicates the end of data transmission, which is added immediately following the
character (or if parity is enabled, immediately following the parity bit). The stop bit
can be chosen to be one bit or two bits long.
LSB
ST b7 b6 b5 b4
ST b7 b6 b5 b4
ST b7 b6 b5 b4
ST b7 b6 b5 b4
7-bit character
LSB
ST b7 b6 b5 b4
ST b7 b6 b5 b4
ST b7 b6 b5 b4
ST b7 b6 b5 b4
8-bit character
LSB
ST b8 b7 b6 b5
ST b8 b7 b6 b5
ST b8 b7 b6 b5
ST b8 b7 b6 b5
9-bit character
SIO Transmit Buffer Register
SIO Receive Buffer Register
b7 b8
7-bit character
8-bit character
9-bit character
• The data bit numbers (bn) above indicate bit numbers in a data list, and not the register bit numbers (bn).
12.6 Transmit Operation in UART Mode
MSB
b3 b2 b1 SP
b3 b2 b1 SP SP
b3 b2 b1 PAR SP
b3 b2 b1 PAR SP
MSB
b3 b2 b1 b0 SP
b3 b2 b1 b0 SP
b3 b2 b1 b0 PAR
PAR
b3 b2 b1 b0
MSB
b4 b3 b2 b1 b0 SP
b4 b3 b2 b1 b0 SP
b4 b3 b2 b1 b0
PAR
b4 b3 b2 b1 b0 PAR
Bits 0-7: Character (data) bits
PAR: Parity bit
b15
12-41
SP
SP
SP
SP SP
SP
SP
SP SP
ST: Start bit
SP: Stop bit
32180 Group User's Manual (Rev.1.0)
Serial I/O