UM1065
Hardware layout and configuration
Doc ID 018640 Rev 4
2.3 Clock
source
Four clock sources are available on STM3221G-EVAL evaluation board for
STM32F217IGH6 and RTC embedded:
●
X1, 25 MHz crystal for ethernet PHY with socket. It can be removed when clock is
provided by MCO pin of the MCU
●
X2, 26 MHz crystal for USB OTG HS PHY
●
X3, 32 kHz crystal for embedded RTC
●
X4, 25 MHz crystal with socket for STM32F217IGH6 microcontroller (it can be removed
from socket when internal RC clock is used)
2.4 Reset
source
The reset signal of STM3221G-EVAL evaluation board is low active and the reset sources
include:
●
Reset button B1
●
Debugging tools from JTAG connector CN14 and trace connector CN13
●
Daughterboard from CN3
●
RS-232 connector CN16 for ISP
●
ST-LINK/V2
2.5 Audio
The STM3221G-EVAL evaluation board enables stereo audio play and microphone
recording by an external headset connected on audio jack CN11.
An audio DAC CS43L22 is connected to both the I2S2 port and the DAC channel while a
microphone amplifier is connected to the ADC of the STM32F217IGH6.
The CS43L22 can be configured via I2C1 and the external PLL (U36) can provide an
external clock which is connected to the I2S_CKIN pin (PC9).
Warning:
Signal I2S_SD (PI3) is close to signal TCK/SWCLK of the
JTAG/SWD interface, so to avoid possible communication
issues on JTAG/SWD when the I2S interface is used the
recommendations are to:
1) Prefer usage of embedded ST-LINK/V2 to external tool
connected on CN14.
2) Configure PI3 GPIO in low speed (2 MHz or 10 MHz).
Table 3.
Audio related jumpers
Jumper
Description
JP16
Description of JP16 is in
JP33
The microphone amplifier can be disabled when JP33 is fitted. Default setting: Not fitted.
