M16C/28 Group
Under development Preliminary specification
Specifications in this manual are tentative and subject to change.
14.1.6 Special Mode 4 (SIM Mode) (UART2)
Rev.0.60 2004.02.01
page 196 of N
REJ09B0047-0060Z
Figure 14.1.6.1. Transmit and Receive Timing in SIM Mode
Transfer clock
An “L” level is output from TxD2 due to
the occurrence of a parity error
Read the U2RB register
Cleared to “0” when interrupt request is accepted, or cleared to “0” in a program
U2C1 register
TE bit
D0 D1 D2 D3 D4 D5 D6 D7
ST
P
“0”
“1”
“0”
“1”
“0”
“1”
“0”
“1”
D0 D1 D2 D3
D4 D5 D6
D7
ST
P
SP
Tc
SP
D0 D1
D2 D3 D4 D5 D6 D7
ST
P
TxD2
“0”
“1”
“0”
“1”
“0”
“1”
D0 D1 D2 D3
D4 D5 D6
D7
ST
P
SP
Tc
SP
D0 D1
D2 D3 D4 D5 D6 D7
ST
P
D0 D1 D2 D3
D4 D5 D6
D7
ST
P
SP
D0 D1 D2 D3 D4 D5 D6 D7
ST
P
D0 D1 D2 D3
D4 D5 D6
D7
ST
P
SP
TxD2
RxD2 pin level
U2C1 register
TI bit
Parity error signal sent
back from receiver
(Note)
U2C0 register
TXEPT bit
S2TIC register
IR bit
Start
bit
Parity
bit
Stop
bit
Write data to U2TB register
Transferred from U2TB register to UART2 transmit register
An “L” level returns due to the
occurrence of a parity error.
The level is
detected by the
interrupt routine.
The level is detected by the
interrupt routine.
The IR bit is set to “1” at the
falling edge of transfer clock
Note : Because TxD2 and RxD2 are connected, this is composite waveform consisting of the transmitter's transmit waveform and the
parity error signal received.
Note : Because TxD2 and RxD2 are connected, this is composite waveform consisting of the TxD2 output and the parity error signal
sent back from receiver.
Tc = 16 (n + 1) / fi or 16 (n + 1) / fEXT
fi : frequency of U2BRG count source (f1SIO, f2SIO, f8SIO, f32SIO)
fEXT : frequency of U2BRG count source (external clock)
n : value set to U2BRG
Tc = 16 (n + 1) / fi or 16 (n + 1) / fEXT
fi : frequency of U2BRG count source (f1SIO, f2SIO, f8SIO, f32SIO)
fEXT : frequency of U2BRG count source (external clock)
n : value set to U2BRG
The above timing diagram applies to the case where data is
transferred in the direct format.
U2MR register STPS bit = 0 (1 stop bit)
U2MR register PRY bit = 1 (even)
U2C0 register UFORM bit = 0 (LSB first)
U2C1 register U2LCH bit = 0 (no reverse)
U2C1 register U2IRSCH bit = 1 (transmit is completed)
Start
bit
Parity
bit
Stop
bit
Cleared to “0” when interrupt request is accepted, or cleared to “0” in a program
Read the U2RB register
(1) Transmission
Transfer clock
U2C1 register
RE bit
RxD2 pin level
Transmitter's
transmit waveform
(Note)
U2C0 register
RI bit
S2RIC register
IR bit
(1) Reception
The above timing diagram applies to the case where data is
transferred in the direct format.
U2MR register STPS bit = 0 (1 stop bit)
U2MR register PRY bit = 1 (even)
U2C0 register UFORM bit = 0 (LSB first)
U2C1 register U2LCH bit = 0 (no reverse)
U2C1 register U2IRSCH bit = 1 (transmit is completed)