st92f124 STMicroelectronics, st92f124 Datasheet - Page 247

• Manufacturer Part Number: st92f124
• Description: 8/16-bit Single Voltage Flash Mcu Family With Ram, E3 Tmemulated Eeprom, Can 2.0b And J1850 Blpd
• Manufacturer: STMicroelectronics

ASYNCHRONOUS SERIAL COMMUNICATIONS INTERFACE (Cont’d)
DATA REGISTER (SCIDR)
R241 - Read/Write
Register Page: 26
Reset Value: Undefined
Contains the Received or Transmitted data char-
acter, depending on whether it is read from or writ-
ten to.
The Data register performs a double function (read
and write) since it is composed of two registers,
one for transmission (TDR) and one for reception
(RDR).
The TDR register provides the parallel interface
between the internal bus and the output shift reg-
ister (see
The RDR register provides the parallel interface
between the input shift register and the internal
bus (see
BAUD RATE REGISTER (SCIBRR)
R242 - Read/Write
Register Page: 26
Reset Value: 00xx xxxx (xxh)
Bits 7:6= SCP[1:0] First SCI Prescaler
These 2 prescaling bits allow several standard
clock division ranges:
SCP1
DR7
7
7
PR Prescaling factor
SCP0
DR6
Figure
Figure
13
SCT2
1
3
4
DR5
117).
117).
SCT1
DR4
ASYNCHRONOUS SERIAL COMMUNICATIONS INTERFACE (SCI-A)
SCT0
DR3
SCP1
SCR2 SCR1 SCR0
DR2
0
0
1
1
DR1
SCP0
0
1
0
1
DR0
0
0
Bits 5:3 = SCT[2:0] SCI Transmitter rate divisor
These 3 bits, in conjunction with the SCP1 & SCP0
bits define the total division applied to the bus
clock to yield the transmit rate clock in convention-
al Baud Rate Generator mode.
Note: This TR factor is used only when the ETPR
fine tuning factor is equal to 00h; otherwise, TR is
replaced by the (TR*ETPR) dividing factor.
Bits 2:0 = SCR[2:0] SCI Receiver rate divisor.
These 3 bits, in conjunction with the SCP1 & SCP0
bits define the total division applied to the bus
clock to yield the receive rate clock in conventional
Baud Rate Generator mode.
Note: This RR factor is used only when the ERPR
fine tuning factor is equal to 00h; otherwise, RR is
replaced by the (RR*ERPR) dividing factor.
TR Dividing Factor
RR Dividing Factor
128
128
16
32
64
16
32
64
1
2
4
8
1
2
4
8
SCT2
SCR2
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
SCT1
SCR1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
SCR0
247/426
SCT0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
9