AT-START-F435
User Manual
2021.11.20
11
Rev
1.00
3.6
LEDs
Power LED1
Red LED indicates that the AT-START-F435 is powered by 3.3 V.
User LED2
Red LED is connected to the PD13 pin of AT32F435ZMT7.
User LED3
Yellow LED is connected to the PD14 pin of AT32F435ZMT7.
User LED4
Green LED is connected to the PD15 pin of AT32F435ZMT7.
3.7
Buttons
Reset B1: Reset button
It is connected to NRST to reset
AT32F435ZMT7 microcontroller.
User B2: User button
It is connected to the PA0 of AT32F435ZMT7 to act as a wakeup button (R19 ON and R21
OFF), or to the PC13 to acts as TAMPER-RTC button (R19 OFF and R21 ON)
3.8
OTGFS configuration
AT-START-F435 board supports OTGFS1 and OTGFS2 full-speed/low-speed host or full-speed
device mode via a USB micro-B connector (CN2 or CN3). In device mode, AT32F435ZMT7 can be
directly connected to the host through USB micro-B, and V
BUS1
or V
BUS2
can be used as 5 V input of
AT- START-F435 board. In host mode, an external USB OTG cable is needed to connect to the
external device. The device is powered via USB micro-B interface, which is done by PH3 and PB10
controlling SI2301 switch.
AT-START-F435 board has a USB type-A extension interface (CN1). This is a OTGFS1 host
interface for connecting to U disk and other devices, without the need of USB OTG cable. The USB
type-A interface has no power switch control.
When the PA9 or PA10 of the AT32F435ZMT7 is used as OTGFS1_VBUS or OTGFS1_ID, the JP4
jumper must select OTG1. In this case, the PA9 or PA10 is connected to USB micro-B CN2
interface, but disconnected from AT-Link interface (CN4).
3.9
QSPI1 interfacing Flash memory
On-board SPI (EN25QH128A), connecting to the AT32F435ZMT7 via QSPI1 interface, is used as
an extended Flash memory.
The QSPI1 interface is connected to Flash memory with PF6~10 and PG6. If these GPIOs are
used for other purposes, it is recommended to turn off RP2, R21 and R22 in advance.
