1 Intro
2
Electrocardiogram (
Ecg
) Signals
The Electrocardiogram (
Ecg
)
•
Ecg
: electrical manifestation of heart activity recorded
from the body surface
•
monitoring of heart rate
The
Ecg
signal can be recorded fairly easily with surface
electrodes placed on the limbs and/or the chest, see pages
6
–
16
below.
Josef Goette
2
2009
4 Peripherals
Universal synchronous asynchronous receiver transmitter (USART)
RM0008
602/682
Figure 236. USART block diagram
WAKE
UP
UNIT
RECEIVER
CONTROL
SR
TRANSMIT
CONTROL
TXE TC RXNE IDLE ORE NE FE
USART
CONTROL
INTERRUPT
CR1
M
WAKE
Receive Data Register (RDR)
Receive Shift Register
Read
Transmit Data Register (TDR)
Transmit Shift Register
Write
SW_RX
TX
(DATA REGISTER) DR
TRANSMITTER
CLOCK
RECEIVER
CLOCK
RECEIVER RATE
TRANSMITTER RATE
f
PCLKx(x=1,2)
CONTROL
CONTROL
/16
CONVENTIONAL BAUD RATE GENERATOR
SBK
RWU
RE
TE
IDLE
RXNE
TCIE
TXEIE
CR1
UE
PCE
PS
PEIE
PE
PWDATA
IRLP
SCEN
IREN
DMAR
DMAT
USART Address
CR2
CR3
IrDA
SIR
ENDEC
BLOCK
LINE
CKEN CPOL CPHA LBCL
SCLK CONTROL
SCLK
CR2
GT
STOP[1:0]
NACK
DIV_Mantissa
15
0
RE
USART_BRR
/
USARTDIV
TE
HD
(CPU or DMA)
(CPU or DMA)
PRDATA
Hardware
flow
controller
CTS LBD
RX
IRDA_OUT
IRDA_IN
nRTS
nCTS
GTPR
PSC
IE
IE
DIV_Fraction
4
USARTDIV = DIV_Ma (DIV_Fraction / 16)
Figure 4.5:
USART driver
Figure 4.6:
USART Names of the additional communication wires
30
STM32 Cortex-M3 Tutorial