Obsolete
Product(s)
- Obsolete
Product(s)
On-chip peripherals
ST72324B-Auto
SCI Extended Transmit Prescaler Division Register (SCIETPR)
This register is used to set the External Prescaler rate division factor for the transmit circuit.
Table 66.
SCIERPR register description
Bit
Name
Function
7:0
ERPR[7:0]
8-bit Extended Receive Prescaler Register
The extended baud rate generator is activated when a value different from 00h
is stored in this register. Therefore the clock frequency issued from the 16
divider (see
Figure 57) is divided by the binary factor set in the SCIERPR
register (in the range 1 to 255).
The extended baud rate generator is not used after a reset.
SCIETPR
Reset value: 0000 0000 (00h)
7
654
32
10
ETPR[7:0]
R/W
Table 67.
SCIETPR register description
Bit
Name
Function
7:0
ETPR[7:0]
8-bit Extended Transmit Prescaler Register
The extended baud rate generator is activated when a value different from 00h
is stored in this register. Therefore the clock frequency issued from the 16
divider (see
Figure 57) is divided by the binary factor set in the SCIETPR
register (in the range 1 to 255).
The extended baud rate generator is not used after a reset.
Table 68.
Baud rate selection
Symbol
Parameter
Conditions
Standard
Baud rate
Unit
fCPU
Accuracy vs.
Standard
Prescaler
fTx
fRx
Communication
frequency
8MHz
~0.16%
Conventional mode
TR (or RR) = 128, PR = 13
TR (or RR) = 32, PR = 13
TR (or RR) = 16, PR = 13
TR (or RR) = 8, PR = 13
TR (or RR) = 4, PR = 13
TR (or RR) = 16, PR = 3
TR (or RR) = 2, PR =13
TR (or RR) = 1, PR = 13
300
1200
2400
4800
9600
10400
19200
38400
~300.48
~1201.92
~2403.84
~4807.69
~9615.38
~10416.67
~19230.77
~38461.54
Hz
~0.79%
Extended mode
ETPR (or ERPR) = 35,
TR (or RR)= 1, PR = 1
14400
~14285.71