DocID029990 Rev 1
19/59
UM2140
Hardware layout and configuration
58
1.
Connect the jumper CN8 on (E5V) or (USB_HS) or (USB_FS)
2. Connect the external power source to CN3 or CN12 or CN18 or CN19
3. Check that the red LED LD2 is turned ON
4. Connect the PC to USB connector CN1
If this order is not respected, the 32F723EDISCOVERY Discovery board may be powered by
V
BUS
first from ST-LINK and the following risks may be encountered:
1.
If more than 500 mA current is needed by the board, the PC may be damaged or current
can be limited by PC. As a consequence the board is not powered correctly.
2. 500 mA is requested at the enumeration: if the PC cannot provide such current, there is
a risk that the request is rejected and the enumeration does not succeed.
7.6 Clock
sources
Up to 2 clock sources as described below:
•
X2, 25 MHz oscillator for STM32F723IEK6 microcontroller.
•
X3, 32 KHz crystal for STM32F723IEK6 embedded RTC
7.7 Reset
sources
The reset signal of the 32F723EDISCOVERY board is active low and the reset sources
include:
•
Reset button B2
•
Arduino Uno V3 shield board from CN12
•
Embedded ST-LINK/V2-1
7.8 Audio
An audio codec WM8994ECS/R from CIRRUS with 4 DACs and 2ADCs is connected to SAI
interface of STM32F723IEK6. It communicates with STM32F723IEK6 via I
2
C bus:
•
The analog line input is connected to ADC of WM8994ECS/R through blue audio jack
CN4
•
The analog line output is connected to DAC of WM8994ECS/R via green audio jack
CN5
•
Two external speakers can be connected to WM8994ECS/R via CN10 for left speaker
and CN7 for right speaker
•
Four digital microphones (ST-MEMS microphone) MP34DT01TR are on
32F723EDISCOVERY board. They are connected to input digital microphones of
WM8994ECS/R