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Automotive Module Series
AG35 Hardware Design
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Table 28: Default Behaviors of RI
State
Response
Idle
RI keeps in high level
URC
RI outputs 120ms low pulse when new URC returns
The default RI behaviors can be configured flexibly by AT+QCFG=“urc/ri/ring” command. Please refer
to document [2] for more details.
3.21. USB_BOOT Interface
AG35 provides a USB_BOOT pin which is multiplexed with COEX_UART_RX. Developers can pull up
USB_BOOT to VDD_EXT before powering on the module, thus the module will enter into emergency
download mode when powered on. In this mode, the module supports firmware upgrade over USB
interface.
Table 29: Pin Definition of USB_BOOT Interface
Pin Name
Pin No.
I/O
Description
Comment
COEX_
UART_RX/
USB_BOOT
146
DI
Force the module to enter into
emergency download mode
1.8V power domain.
Active high.
If unused, keep it open.
The following figure shows a reference circuit design of USB_BOOT interface.
Module
USB_BOOT
VDD_EXT
4.7K
TVS
Close to module
Test point
4.7K
TVS
Figure 32: Reference Circuit of USB_BOOT Interface