STMicroelectronics STM32 Cortex-M3, Manual

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4.15 Inter IC Bus (I
2
C)
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
4.14.1 CAN Analyzer
To understand the data transmitted on the CAN
you need a CAN Analyzer. I used the PCAN-
USB from
www.peak-system.com . This CAN in-
terface allows you to see the messages transmit-
ted on the CAN bus.
Figure 4.16: CAN Analyzer Software
4.14.2 Pinning
Default
Wire GPIO Pin
CANRX PA11 44
CANTX PA12 45
Remapped
Wire GPIO Pin
CANRX PB8/PD0 61/5
CANTX PB9/PD1 62/6
4.15 Inter IC Bus (I
2
C)
i2c1
F Writes data to the I
2
C bus
b
STM32F103RB have two I
2
C bus interfaces which can operate in multimaster and slave modes.
They can support standard and fast modes. They support dual slave addressing (7-bit only) and
both 7/10-bit addressing in master mode. A hardware CRC generation/verification is embedded.
They can be served by DMA and they support SM Bus 2.0/PM Bus.
Introduction
The I
2
C interface
3
is a serial interface with three wires.
The clock on the one directional wire SLC is generated by the master with a fix frequency. This
line is stable (normally high) when no data are transmitted on th data line. The second wire SDA
is bi directional and used for the data communication between the master and the slave
4
.
The wiring is according to Figure 4.17 .
3
IIC, I
2
C (Inter IC Bus) were developed and registered by Phillips and saved as a trademark. Atmel uses the name
TWI.
4
The slave is controlled by the master.
Lukas Kohler 41