ST STM32F40 Series User Manual

RM0090 Universal synchronous asynchronous receiver transmitter (USART)
Doc ID 018909 Rev 4 760/1422
9. 921.6 KBps NA NA NA 941.176 KBps 1.0625 2.12%
10. 1.792 MBps NA NA NA NA NA NA
11. 1.8432 MBps NA NA NA NA NA NA
12. 3.584 MBps NA NA NA NA NA NA
13. 3.6864 MBps NA NA NA NA NA NA
14. 7.168 MBps NA NA NA NA NA NA
15. 7.3728 MBps NA NA NA NA NA NA
1. The lower the CPU clock the lower the accuracy for a particular baud rate. The upper limit of the achievable baud rate can
be fixed with these data.
Table 113. Error calculation for programmed baud rates at f
PCLK
= 8 MHz or f
PCLK
= 16 MHz,
oversampling by 8
(1)
Oversampling by 8 (OVER8=1)
Baud rate f
PCLK
= 8 MHz f
PCLK
= 16 MHz
S.No Desired Actual
Value
programmed
in the baud
rate register
% Error =
(Calculated -
Desired)B.Rate
/Desired B.Rate
Actual
Value
programmed
in the baud
rate register
% Error
1. 2.4 KBps 2.400 KBps 416.625 0.01% 2.400 KBps 833.375 0.00%
2. 9.6 KBps 9.604 KBps 104.125 0.04% 9.598 KBps 208.375 0.02%
3. 19.2 KBps 19.185 KBps 52.125 0.08% 19.208 KBps 104.125 0.04%
4. 57.6 KBps 57.557 KBps 17.375 0.08% 57.554 KBps 34.750 0.08%
5. 115.2 KBps 115.942 KBps 8.625 0.64% 115.108 KBps 17.375 0.08%
6. 230.4 KBps 228.571 KBps 4.375 0.79% 231.884 KBps 8.625 0.64%
7. 460.8 KBps 470.588 KBps 2.125 2.12% 457.143 KBps 4.375 0.79%
8. 896 KBps 888.889 KBps 1.125 0.79% 888.889 KBps 2.250 0.79%
9. 921.6 KBps 888.889 KBps 1.125 3.55% 941.176 KBps 2.125 2.12%
10. 1.792 MBps NA NA NA 1.7777 MBps 1.125 0.79%
11. 1.8432 MBps NA NA NA 1.7777 MBps 1.125 3.55%
12. 3.584 MBps NA NA NA NA NA NA
13. 3.6864 MBps NA NA NA NA NA NA
14. 7.168 MBps NA NA NA NA NA NA
15. 7.3728 MBps NA NA NA NA NA NA
Table 112. Error calculation for programmed baud rates at f
PCLK
= 8 MHz or f
PCLK
= 16 MHz,
oversampling by 16
(1)
(continued)
Oversampling by 16 (OVER8=0)
Baud rate f
PCLK
= 8 MHz f
PCLK
= 16 MHz
S.No Desired Actual
Value
programmed
in the baud
rate register
% Error =
(Calculated -
Desired)B.Rate
/Desired B.Rate
Actual
Value
programmed
in the baud
rate register
% Error

ST STM32F40 Series Specifications

General

Brand	ST
Model	STM32F40 Series
Category	Microcontrollers
Language	English