ST STM32G0C1E-EV User manual

Introduction
The STM32G0C1E-EV Evaluation board is a high-end development platform for the STM32G0C1VET6 microcontroller
operating at up to 64 MHz frequency with internal 512-Kbyte Flash memory, 144-Kbyte RAM, USB 2.0 FS device and host,
two CAN FDs, USB Type-C®, and Power Delivery controller interfaces (UCPD) compliant with USB Type-C® r1.2 and USB
PD specification r3.0, three I2Cs, three SPIs, six USARTs, two low-power UARTs, one 12-bit ADC, two 12-bit DACs, three
general-purpose comparators, seven general-purpose timers, two low-power timers, HDMI CEC, and SWD debugging support.
The full range of hardware features on the STM32G0C1E-EV Evaluation board includes the mother board, the legacy peripheral
daughterboard, and the USB-C® and Power Delivery daughterboard, which help to develop applications, and evaluate all
peripherals, such as USB Type-C® connector with USB PD, motor control connector, CAN FD, USB 2.0 FS, RS-232, RS-485,
audio DAC, microphone ADC, TFT LCD, IrDA, IR LED, IR receiver, LDR, microSD™ card, CEC on two HDMI connectors,
Smartcard slot, RF EEPROM, and temperature sensor.
The board integrates an ST-LINK/V2-1 as an embedded in-circuit debugger and programmer for the STM32 MCU.
The daughterboard and extension connectors provide an easy way to connect a daughterboard or wrapping board for the user's
specific application.
The USB-C® and Power Delivery daughterboard features two independent USB-C® ports controlled by STM32G0. USB-C® port
1 is a dual role power (DRP) port and can provide up to 45 W of power. USB-C® port 2 is a sink port only. Both support the USB
PD protocol and the alternate mode functionality.
Application firmware examples are provided to evaluate USB-C® technology through various use cases.
Figure 1. STM32G0C1E-EV Evaluation board with legacy
peripheral daughterboard
Figure 2. STM32G0C1E-EV Evaluation board with USB-C®
daughterboard
Pictures are not contractual.
Evaluation board with STM32G0C1VE MCU
UM2783
User manual
UM2783 - Rev 1 - December 2020
For further information contact your local STMicroelectronics sales office. www.st.com

1Features
Mother board
• STM32G0C1VET6 Arm® Cortex®-M0+ core-based microcontroller with 512 Kbytes of Flash memory and
144 Kbytes of RAM in LQFP100 package
• MCU voltage choice fixed at 3.3 V or adjustable from 1.65 V to 3.5 V
• I2C compatible serial interface
• RTC with backup battery
•8-Gbyte or more SPI interface microSD™ card
• Potentiometer
• 4 color user LEDs and one LED as MCU low-power alarm
• Reset, Tamper, and User buttons
• 4-direction joystick with selection button
• Board connectors:
– 5 V power jack
– RS-232 and RS485 communications
– CAN FD
– Stereo audio jack including analog microphone input
– microSD™ card
– Extension I2C connector
– Motor-control connector
– Daughterboard connectors for legacy peripheral daughterboard or USB-C® and Power Delivery
daughterboard
– Extension connectors for daughterboard or wire-wrap board
• Flexible power-supply options:
– 5 V power jack
– ST-LINK/V2-1 USB connector
– Daughterboard
• On-board ST-LINK/V2-1 debugger/programmer with USB re-enumeration capability: Virtual COM port and
debug port
• Comprehensive free software libraries and examples available with the STM32CubeG0 MCU Package
• Support of a wide choice of Integrated Development Environments (IDEs) including IAR Embedded
Workbench®, MDK-ARM, and STM32CubeIDE
Legacy peripheral daughterboard
• IrDA transceiver
• IR LED and IR receiver
• Light-dependent resistor (LDR)
• Temperature Sensor
• Board connectors:
– Two HDMI connectors with DDC and CEC
– Smartcard slot
USB-C® and Power Delivery daughterboard
• Multiplexor for first-generation USB 3.1 Type-B receptacle / DisplayPort™ input and USB Type-C® port 1
output
• Multiplexor for USB Type-C® port 2 input and DisplayPort™ output / USB 2.0 Type-A receptacle
• VCONN on USB Type-C® port 1
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Features
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• USB PD on USB Type-C® port 1
• Board connectors:
– USB Type-C® port 1 DRP (dual-role port) and USB 2.0 FS data
– USB Type-C® port 2 sink
– DisplayPort™ input
– DisplayPort™ output
– First-generation USB 3.1 Type-B receptacle, not installed by default
– USB 2.0 Type-A receptacle, not installed by default
– 19 V power jack for USB PD
Note: Arm is a registered trademark of Arm Limited (or its subsidiaries) in the US and/or elsewhere.
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Features
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2Ordering information
To order the STM32G0C1E-EV Evaluation board, refer to Table 1. Additional information is available from the
datasheet and reference manual of the target STM32.
Table 1. Ordering information
Order code Board reference Target STM32
STM32G0C1E-EV
• MB1581: mother board
• MB1351: legacy peripheral daughterboard
• MB1352: USB-C® daughterboard
• MB895: LCD daughterboard
STM32G0C1VET6U
2.1 Codification
The meaning of the codification is explained in Table 2.
Table 2. Codification explanation
STM32XXYYT-EV Description Example: STM32G0C1E-EV
XX MCU series in STM32 32-bit Arm Cortex MCUs STM32G0 Series
YY MCU product line in the series STM32G0C1
TSTM32 Flash memory size
• E for 512 Kbytes 512 Kbytes
EV Evaluation board Evaluation board
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Ordering information
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3Development environment
3.1 System requirements
• Windows® OS (7, 8, or 10), Linux® 64-bit, or macOS®
• USB Type-A or USB Type-C® to Micro-B cable
Note: macOS® is a trademark of Apple Inc. registered in the U.S. and other countries.
All other trademarks are the property of their respective owners.
3.2 Development toolchains
• IAR Systems® - IAR Embedded Workbench®(1)
• Keil® - MDK-ARM(1) (2)
• STMicroelectronics - STM32CubeIDE
1. On Windows® only.
2. Free MDK-ARM for Arm® Cortex®-M0/M0+ cores.
3.3 Demonstration software
The demonstration software, included in the STM32Cube MCU Package corresponding to the on-board
microcontroller, is preloaded in the STM32 Flash memory for easy demonstration of the device peripherals in
standalone mode. The latest versions of the demonstration source code and associated documentation can be
downloaded from www.st.com.
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Development environment
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4Conventions
Table 3 provides the conventions used for the ON and OFF settings in the present document.
Table 3. ON/OFF convention
Convention Definition
Jumper JPx ON Jumper fitted
Jumper JPx OFF Jumper not fitted
Jumper JPx [1-2] Jumper fitted between Pin 1 and Pin 2
Solder bridge SBx ON SBx connections closed by 0 Ω resistor
Solder bridge SBx OFF SBx connections left open
Resistor Rx ON Resistor soldered
Resistor Rx OFF Resistor not soldered
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Conventions
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5Delivery recommendations
Some verifications are needed before using the board for the first time to make sure that nothing was damaged
during shipment and that no components are unplugged or lost. When the board is extracted from its plastic
bag, check that no component remains in the bag. Before starting the demo, take the microSD™ card from the
separated ESD bag and plug it in the CN11 connector, on the right side of the board.
Warning:
There is an explosion risk if the battery is replaced with an incorrect one. Make sure to dispose of
used batteries according to the instructions.
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Delivery recommendations
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6Hardware layout and configuration
The hardware block diagram (Refer to Figure 3) illustrates the connections between the STM32G0C1VET6
microcontroller and the peripherals on the STM32 G0 Evaluation board (such as motor-control connector,
CAN FDs, RS232, RS485, Audio DAC, microphone ADC, TFT LCD, IrDA, IR LED, IR receiver, LDR, microSD™
card, CEC on two HDMI connectors, Smartcard slot, Temperature sensor). Figure 4, Figure 5, and Figure 6 help
the user to locate these features on the STM32G0C1E-EV Evaluation board.
Figure 3. Hardware block diagram
Joystick, Key and Tamper button,
LEDs, motor-control connector
GPIOs
USART1
SWD
TIM3_CH1
IR_OUT
IR receiver
IR LED Voltage
Translator
DB9
connector
USART2Smartcard
ADC
FDCAN1 CAN-FD
transceiver
STM32G0C1VET6
RS232
transceiver
RS485
transceiver
Embedded
STLINK/
V2-1
Micro-B
USB
connector
USART3
SPI1 Voltage
Translator
MicroSDTM
card
Dot Matrix
LCD
ADC
DAC
Microphone
Amplifier
Speaker
Amplifier
3.5mm
jack
Potentiometer
2.54 mm
Jumper
FDCAN2 CAN-FD
transceiver
2.54 mm
Jumper
COMP1_INP
I2C2
LDR
HDMI sink
CEC
HDMI source
I2C1
USBC-1
GPIO
USBC-2
Temperature
sensor
I2C EXT
connector
DisplayPort™
sink
MUX
MUX USB
Type-C®
connector
USB Power
Delivery
MB1581
mother
board
MB1351 legacy
peripheral
daughterboard
MB1352 USB-C®
daughterboard
USB
Type-C®
connector
DisplayPort™
source
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Hardware layout and configuration
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Figure 4. STM32G0C1E-EV Evaluation board layout (MB1581)
CN1: motor-control connector
CN11: microSD™ connector
CN4: I2C EXT connector
CN2/CN3: Daughterboard connectors
CN5: STLINK USB connector
CN12: FDCAN1 jumper
CN13: FDCAN2 jumper
CN16: USART1
RS232 / RS485 connector
JP24: 5 V Power jumper
CN20: 5 V Power jack
LD1-4: User LEDs
CN15: SWD debug connector
CN14: SWD debug connector
CN17: LCD connector
CN18: Stereo audio jack 3.5mm
with microphone
CN19: LCD connector
CN9 / CN10: Extension connectors
LD5: Low-voltage alarm LED
U7: STM32G0C1VET6
RV2: VDD ADJ
B1: Reset
button
B2: Tamper
button
B3: Joystick
RV3: VDD ANA potentiometer
LD6: STLINK/V2-1 COM LED
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Hardware layout and configuration
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Figure 5. Legacy peripheral daughterboard (MB1351)
CN3
HDMI source
CN1
HDMI sink
R1 LDR CN2
Smartcard
LD1 IR LED
D1 IR receiver
Figure 6. UCPD daughterboard (MB1352)
CN7
USB Type-C® 1
(DRP
dual-role port)
CN6
DisplayPortTM
input
CN4
USB 3.0
connector
CN3
Extension
power input
CN2
DisplayPortTM
output CN1
USB Type-A
CN5
USB Type-C® 2
(sink)
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Hardware layout and configuration
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6.1 Embedded ST-LINK/V2-1
The ST-LINK/V2-1 facility for debugging and flashing of STM32G0C1VET6 is integrated on the STM32G0C1E-EV
Evaluation board.
Compared to the ST-LINK/V2 stand-alone tool available from STMicroelectronics, ST-LINK/V2-1 offers new
features and drops some others.
New features:
• USB software re-enumeration
• Virtual COM port interface on USB
• Mass storage interface on USB
• USB power management request for more than 100 mA power on USB
This feature is no longer supported on ST-LINK/V2-1:
• SWIM interface
For full detail on both versions of the debugging and flashing tool, the stand-alone ST-LINK/V2 and the embedded
ST-LINK/V2-1, refer to ST-LINK/V2 in-circuit debugger/programmer for STM8 and STM32 user manual (UM1075).
Note: It is possible to power the board via CN5 (Embedded ST-LINK/V2-1 USB connector) even if an external tool is
connected to CN14 or CN15 (External SWD connector).
6.1.1 Drivers
Before connecting the STM32G0C1E-EV Evaluation board to a Windows® PC (7, 8, or 10) through a USB, a
driver for the ST-LINK/V2-1 must be installed. It is available on the www.st.com website.
In case the STM32G0C1E-EV Evaluation board is connected to the PC before the driver is installed, some
STM32G0C1E-EV interfaces may be declared as "unknown" in the PC device manager. To recover from this
situation, the user must install the driver files, and update the driver of the connected device from the device
manager (see ).
Figure 7. USB composite device
6.1.2 ST-LINK/V2-1 firmware upgrade
For its operation, ST-LINK/V2-1 employs a dedicated MCU with Flash memory. Its firmware determines ST-
LINK/V2-1 functionality and performance. The firmware may evolve during the life span of STM32G0C1E-EV
Evaluation board to include new functionality, fix bugs, or support new target microcontroller families. It is
therefore recommended to keep ST-LINK/V2-1 firmware up to date. The latest version is available from
www.st.com.
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Embedded ST-LINK/V2-1
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6.2 Power supply
The STM32G0C1E-EV Evaluation board is designed to be powered by a 5 V DC power supply and is protected
from the wrong power plug-in event.
Thanks to the JP24 jumper, it is possible to configure the mother board to use any of the following four sources for
the power supply:
JP24 = E5V
5 V DC power adapter connected to CN20, the power jack on the board. The external power supply is provided to
the board.
JP24 = STLK (Default configuration)
5 V DC power with 500 mA limitation from CN5, the USB Micro-B connector of ST-LINK/V2-1. If the USB
enumeration succeeds, the ST-LINK PWR_EN pin is set to zero, which enables an STMPS2141STR power
switch, thus providing 5 V power to the board. This power switch also features a current limitation to protect the
PC in case of short-circuit on the board. If an overcurrent (more than 500 mA) happens on the board, the LD8
LED lights up.
JP24 = VUSB
5 V DC power from USB Micro-B connector of ST-LINK/V2-1, CN5 pin 1 (VBUS) directly, without overcurrent
protection
JP24 = D5V
5 V DC power from CN3 or CN10 connectors, the extension connectors for a daughterboard power source
The UCPD daughterboard uses its own 19 V power adapter to support USB PD. In this case, the mother board
uses D5V from the UCPD daughterboard to supply all circuits on the STM32G0C1E-EV Evaluation board. D5V of
the UCPD daughterboard has three sources as below:
• 19 V DC power adapter connected to MB1352_CN3 on the UCPD daughterboard
• Power from USB Type-C® port1 MB1352_CN7 on the UCPD daughterboard
• Power from USB Type-C® port2 MB1352_CN5 on the UCPD daughterboard
19 V DC power adapter and USB Type-C® port1 sources are automatically selected by a circuit (MB1352_D8 and
MB1352_T10 on the UCPD daughterboard).
Caution: In case of development based on the boards, note that unexpected high voltage may appear in CN7 when
plugging in 19 V power. So when using a 19 V power adaptor, apply default demonstration configuration with the
boards, or refer to steps[1] in MB1352 schematic, and install protection on the software side[2].
[1] Steps:
1. DCDC_EN detects its voltage to ensure PSU 19V exists.
2. PWM_CTL provides about 0.8 V level before DCDC_EN=1.
3. DCDC_EN=1, then PWM_CTL changes to provide PWM waveform by 0 and open-drain.
[2] Protection on the software side:
• Refer to /* SAFETY PROTECTION CODE BEGIN */ section in main.c of USB_Host applications. This
file can be found in STM32Cube_FW_G0_1.4.0 in STM32CubeMX.
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Power supply
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Figure 8. STM32G0C1E-EV 5 V power structure
The STM32G0C1E-EV Evaluation board can be powered from the mother board’s CN5 ST-LINK/V2-1 USB
connector with a PC, but only the ST-LINK/V2-1 circuit has the power before USB enumeration because the
host PC only provides 100 mA to the boards at that time. During the USB enumeration, the STM32G0C1E-EV
Evaluation board requires 300 mA power from the host PC. If the host can provide the required power, the
enumeration succeeds, the STMPS2141STR power switch U2 is switched ON, the green LED LD7 is turned ON,
and thus the STM32G0C1E-EV Evaluation board is powered and can consume a maximum of 300 mA current.
If the host PC is not able to provide the requested current, the enumeration fails. Therefore, the STM32 part
including the extension board is not powered. As a consequence, the LD7 green LED remains turned OFF. In this
case, it is mandatory to use an external power supply to supply extra power.
E5V (from PSU) or D5V can be used as an external power supply in case the current consumption of the
STM32G0C1E-EV Evaluation board exceeds the allowed current on USB. In this condition, it is still possible to
use USB for communication, for programming or debugging only, but it is mandatory to power the board first using
E5V or D5V JP24 configuration, and then connecting the USB cable to the PC. Proceeding this way ensures that
the enumeration succeeds thanks to the external power source.
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Power supply
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The following power sequence procedure must be respected:
1. Connect the JP24 jumper in E5V or D5V configuration.
2. Check that JP1 is removed.
3. Connect the external power source to PSU or D5V (daughterboard mounted).
4. Check that the LD7 green LED is turned ON.
5. Connect the PC to the CN5 ST-LINK USB connector.
If this order is not respected, the board may be powered by VBUS first then E5V or D5V, and the following risks
may be encountered:
1. If more than 300 mA current is needed by the board, the PC may be damaged or the current can be limited
by the PC. As a consequence, the board is not powered correctly.
2. 300 mA is requested at enumeration (since JP1 must be OFF), so there is a risk that the request is rejected
and enumeration does not succeed if the PC cannot provide such current.
3. Consequently, the board is not powered (LD7 LED remains OFF).
In case the STM32G0C1E-EV Evaluation board is powered by a USB charger through CN5, there is no USB
enumeration needed. The user can set JP24 to VUSB to allow the board to be powered anyway from CN5. The
power source is selected by setting the JP24, JP16, and JP17 related jumpers as described in Table 4.
Table 4. Power source related jumpers
Jumper Description(1)
JP24
For 5 V power supply from USB (CN5) of ST-LINK/V2-1 through STMPS2141STR power switch (with
OVC protection) to the STM32G0C1E-EV Evaluation board, JP24 is set as shown:
VUSB E5V D5V STLK
For 5 V power supply from the daughterboard connectors (CN3 or CN10) to the STM32G0C1E-EV
Evaluation board, JP24 is set as shown:
VUSB E5V D5V STLK
For 5 V power supply, from PSU jack (CN20) to the STM32G0C1E-EV Evaluation board, JP24 is set as
shown:
VUSB E5V D5V STLK
For 5V power supply directly from CN5 VBUS pin to the STM32G0C1E-EV Evaluation board without OVC
protection, JP24 is set as shown:
VUSB E5V D5V STLK
JP16
The VBAT pin of MCU is connected to VDD when JP16 is set as shown:
The VBAT pin of MCU is connected to a 3 V battery when JP16 is set as shown:
JP17
VDD is connected to +3.3 V when JP17 is set as shown:
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Power supply
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Jumper Description(1)
JP17
VDD is connected to VDD_ADJ when JP17 is set as shown:
1. The default setting is in bold.
Note: The VDD_MCU Idd measurement can be done by the current meter that is mounted on JP18 when it is OFF.
But JP18 must not be OFF without a current meter. Otherwise, MCU may be damaged due to the lack of power
supply on its power pins.
Note: LD5 is lit when VDD < 2.7 V and in this case IOs and some Analog IPs of MCU work with degraded
performances.
Note: The UCPD daughterboard works with VDD = 3.3 V, so it is mandatory to close JP17 pin1 and pin2. The
LED LD7 is lit when the STM32G0C1E-EV Evaluation board is powered by the 5 V correctly. Table 5 shows
the low-voltage limitations that may apply depending on the characteristics of some peripheral components.
Components may work incorrectly when the power level is lower than the limitation.
Table 5. Low voltage limitation
Board Peripheral Component I/O name Low-voltage limitation
Mother board MB1581 Audio amplifier U17 Audio output 2.2 V
Mother board MB1581 Microphone amplifier U12 Audio input 2.7 V
Legacy
daughterboardMB1351 Smartcard MB1351_CN2 USART2 2.7 V
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Power supply
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6.3 Clock references
Two clock sources are available on the STM32G0C1E-EV Evaluation board for STM32G0C1VE and its
embedded RTC, and other clock sources for their peripherals.
• 32.768 kHz crystal X2 for embedded RTC
• 8 MHz crystal X3 for the STM32G0C1VE microcontroller. It can be disconnected by removing R46 and R47
when the internal RC clock is used.
Table 6. 32 KHz crystal X2 related solder bridges
Solder bridge Description
SB53
PC14 is connected to the 32KHz crystal when SB53 is OFF.
PC14 is connected to the CN9 extension connector when SB53 is ON. In such a case, R39
must be removed to avoid disturbance due to the 32 Khz quartz.
SB52
PC15 is connected to the 32KHz crystal when SB52 is OFF.
PC15 is connected to the CN9 extension connector when SB52 is ON. In such a case, R40
must be removed to avoid disturbance due to the 32Khz quartz.
1. The default setting is in bold.
Table 7. 8 MHz crystal X3 related solder bridges
Solder bridge Description
SB55
PF0 is connected to an 8 MHz crystal when SB55 is OFF.
PF0 is connected to the CN10 extension connector when SB55 is ON. In such a case, R46
must be removed to avoid disturbance due to the 8 Mhz quartz.
SB54
PF1 is connected to an 8 MHz crystal when SB54 is OFF.
PF1 is connected to the CN10 extension connector when SB54 is ON. In such a case, R47
must be removed to avoid disturbance due to the 8 Mhz quartz.
1. The default setting is in bold.
6.4 Reset sources
The general reset of the STM32G0C1E-EV Evaluation board is active LOW. The reset sources include:
• B1 Reset button
• Debugging tools from CN14 and CN15 SWD connectors
• Daughterboard on CN2
• Embedded ST-LINK/V2-1
• CN16 RS-232 connector for ISP
Note: The JP20 jumper must be ON for reset handled by pin8 of CN16 RS-232 connector (CTS signal).
6.5 Boot option
The STM32G0C1E-EV Evaluation board can boot from:
• Embedded user Flash memory
• System memory with boot loader for ISP
• Embedded SRAM for debugging
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Clock references
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The boot option is configured by closing JP2 [2-3] and setting one jumper cap on CN9 among pin 6, pin 8, and pin
10 and one option bit. Refer to Table 8 and Table 9.
Table 8. Boot related jumper
Jumper configuration Bit 25 in user option bytes Boot from(1)
CN9 pins 8 and 10 closed by jumper X STM32G0C1E-EV Evaluation board
boot from user Flash
CN9 pins 8 and 6 closed by jumper 0 STM32G0C1E-EV Evaluation board
boot from embedded SRAM
CN10 pins 8 and 6 closed by jumper 1 STM32G0C1E-EV Evaluation board
boot from system memory
1. The default setting is in bold.
Table 9. Boot0 related jumper
Solder bridge Description(1)
JP2
PA14-BOOT0 is used as SWCLK when JP2 is set as shown here.
The Bootloader_BOOT0 is managed by pin 6 of the CN16 connector (RS-232 DSR signal)
and it is connected to PA14-BOOT0 when JP2 is set as shown here. This configuration is
used for boot loader application only.
1. The default setting is in bold.
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Boot option
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6.6 Peripherals on mother board (MB1581)
6.6.1 Audio
The STM32G0C1E-EV mother board (MB1581) supports stereo audio playback and microphone recording by an
external headset connected to the CN18 audio jack. The audio play is connected to the DAC output of the MCU
through an audio amplifier, and the microphone on the headset is connected to the ADC input of the MCU through
a microphone amplifier. The audio amplifier can be enabled or disabled by the JP25 setting and mono/stereo
playback can be chosen by the JP19 setting. Refer to Table 10 for detail.
Table 10. Audio related jumpers
Jumper Description(1)
JP25 Speaker amplifier U17 is enabled when JP25 is ON.
Speaker amplifier U17 is disabled when JP25 is OFF.
JP23 PA4 is connected to VIN1 of the audio amplifier when JP23 is ON.
PA4 is disconnected to VIN1 of the audio amplifier when JP23 is OFF.
JP19
Mono playback is enabled when JP19 is set as shown here:
Stereo playback is enabled when JP19 is set as shown here:
1. The default setting is in bold.
The audio amplifier operates correctly when VDD is superior to 2.2 V and the microphone amplifier operates
correctly when VDD is superior to 2.7 V
6.6.2 RS-232 and RS-485
Communication through RS-232 (With Hardware flow control CTS and RTS) and RS-485 are supported by the
CN16 D-type 9-pins RS-232/RS-485 connector, which is connected to USART1 of MCU on the STM32G0C1E-EV
Evaluation board. The Bootloader_RESET (shared with CTS signal) and Bootloader_BOOT0 (shared with DSR
signal) signals are added to the CN16 RS-232 connector for ISP support.
By default, PC4 and PC5 are connected as TX and RX signals. PA9 and PA10 can also be connected as these
two signals for bootloader which is NOT supported on PC4 and PC5 by the setting of jumpers in Table 11.
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Peripherals on mother board (MB1581)
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Table 11. RS-232 and RS-485 related jumpers
Jumper Description(1)
JP14
RS232_RX is connected to the RS232 transceiver and RS232 communication is enabled when JP14 is
set as shown here:
RS485_RX is connected to the RS485 transceiver and RS485 communication is enabled when JP14 is set as
shown here:
JP15
PC4 is connected as a TX signal without bootloader being supported when JP15 is set as shown here:
PA9 is connected as a TX signal with bootloader being supported when JP15 is set as shown here (The CN1
motor‑control connector must be OFF in this case):
JP13
PC5 is connected as an RX signal without bootloader being supported when JP13 is set as shown here:
PA10 is connected as an RX signal with bootloader being supported when JP13 is set as shown here (CN1
motor‑control connector must be OFF in this case):
1. The default setting is in bold.
The RS-485 communication is supported by the ST3485EBDR RS-485 transceiver which is connected to pin 4
and pin 9 of D-type 9-pins CN16 connector and shares the same connector with USART1.
Table 12. RS-485 related jumpers
Jumper Description(1)
SB29, SB31 The external failsafe biasing is enabled when the SB29 and SB31solder bridges are ON.
OFF
SB30 The bus termination is enabled when the solder bridge SB30 is ON.
OFF
SB28 The AC termination is disabled when the solder bridge SB28 is ON for high baud-rate communication.
OFF
1. The default setting is in bold.
6.6.3 microSD™ card
The 8-Gbyte (or more) microSD™ card connected to SPI1 port (Shared with color LCD) of MCU is available on
the board. The microSD™ card detection is managed by standard I/O port PC9 and it must be set via internal
pull-up.
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Peripherals on mother board (MB1581)
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6.6.4 Analog input
The CN21 two-pin header and RV3 10 KΩ potentiometer are connected to PB2 of MCU as analog input. A
low‑pass filter can be implemented by replacing R104 and C81 with the right value of resistor and capacitor as
requested by the end user’s application.
6.6.5 External I2C connector
The I2C1 bus of the MCU is connected to CN4 on the STM32G0C1E-EV Evaluation board. The I2C functional
daughterboard can be mounted on the CN4 connector and accessed by the microcontroller through the I2C1
bus. It shares the same I2C1 bus with the U3 temperature sensor and DDC on the MB1351_CN3 HDMI_Source
connector on the legacy peripheral daughterboard.
The pull-up voltage level of the I2C1 bus is automatically decided by the daughterboard (the legacy peripheral
daughterboard or the UCPD daughterboard) on CN2 and CN3. If there is no daughterboard on these connectors,
pin 17 and pin 18 must be shortened on CN2 and CN3 by jumpers. Thus I2C and reset pull-up voltages on CN4
are the voltage of VDD.
6.6.6 Motor control
The STM32G0C1E-EV Evaluation board supports both asynchronous and synchronous three-phase brushless
motor control via the CN1 34-pins connector, which provides all required control and feedback signals to and from
the motor power driving board. Available signals on this connector include emergency stop, motor speed, 3-phase
motor current, bus voltage, power heatsink temperature coming from the motor driving board, and six channels of
PWM control signal going to the motor driving circuit. The daughterboard on CN2 and CN3 must be removed and
some jumpers set for motor-control application:
• JP5, JP6, and JP7 jumpers ON
• JP22 and JP19 jumpers OFF
• JP13[2-3] and JP15[2-3] jumpers OFF.
6.6.7 Display and input devices
The 2.4-inch color TFT LCD connected to the SPI1 port of MCU and four general‑purpose color LEDs (LD1, LD2,
LD3, and LD4) are available as display devices. The B3 4-direction joystick with selection key is connected to PA0
and supports the wake-up feature. The B2 Tamper button is also available as an input device.
Table 13. CN17/CN19 2.4-inch TFT-LCD connector
Pin Description Pin connection Pin Description Pin connection
1 CS PB8 9 VDD 3.3V
2 SCL PB3 10 VCI 3.3V
3 SDI PA7 11 GND GND
4 RS - 12 GND GND
5 WR - 13 BL_VDD 5V
6 RD - 14 BL_Control 5V
7 SDO PB4 15 BL_GND GND
8 RESET RESET# 16 BL_GND GND
Note: The bi-directional voltage translator implemented on the SPI MOSI signal between MCU and LCD to support the
3-wire serial interface of the LCD panel only supports a 3-wire SPI port. The direction of this voltage translator is
controlled by I/O PC12 (the IO PA7 is working as MOSI when PC12 is HIGH or as MISO when PC12 is LOW).
UM2783
Peripherals on mother board (MB1581)
UM2783 - Rev 1 page 20/59