3.4.4 Other Selection Switches
The USB2 port of is terminated with USB 3.0 Micro AB connector on the common processor board. The Host
and Device function of SoC is set by the ID pin using DIP Switch SW1.
The ID and VBUS supply pin of USB connectors is connected to the DIP switch SW1 to configure the operational
modes.
As previously mentioned, the USB2 port, USB3.0 microAB interface is not supported with the J721E SoM.
3.5 EVM UART/COM Port Mapping
Four main domain UART ports of the SoC are interfaced with FT4232H for UART-to-USB functionality and
terminated on a micro B connector (J44) provided on the CPB. When the EVM is connected to a Host using
the provided USB cable, the computer can establish a Virtual Com Port that can be used with any terminal
emulation application. The FT4232H is bus powered. Virtual Com Port drivers for the FT4232H can be obtained
from
https://www.ftdichip.com/Products/ICs/FT4232H.htm
.
Out of four UART ports, one UART port (UART0) supports RS232 with Hardware flow control.
MCU and WKUP UART ports of the SoC are interfaced with FT2232H for UART-to-USB functionality and
terminated on a micro B connector (J43) provided on the CPB. When the EVM is connected to a Host using
the provided USB cable, the computer can establish a Virtual Com Port that can be used with any terminal
emulation application. The FT2232H is bus powered. Virtual Com Port drivers for the FT4232H can be obtained
from
https://www.ftdichip.com/Products/ICs/FT2232H.html
.
RS232 hardware control feature is supported on MCU UART0.
Both FT2232H and FT4232H circuits powered through USB VBUS. Since the circuits are powered through BUS
power, the connection to the COM port will not be lost when the EVM power is removed. The maximum length of
the IO cables should not exceed 3 meters.
Table 3-10. UART Port Mapping
UART Port
FTDI Bridge
USB Connector
COM Port
Remarks
MAIN_UART0
FT4232H
J44
COM 1
Supports Hardware Flow
control
MAIN_UART1
COM 2
MAIN_UART2
COM 3
MAIN_UART4
COM 4
MCU_UART0
FT2232H
J43
COM 5
Supports Hardware Flow
control
WKUP_UART0
COM 6
The EEPROM of FTDI bridges are programmed with the CPB serial number, users to identify the connected
COM port with board serial number when one or more boards connected to the computer.
Example Programming content:
• FT4232H (Main)
– CPB Serial number: 14197900028
• Programmed Serial number on FT4232H EEPROM: 141979000280A
– FT2232H (MCU and WKUP)
• CPB Serial number: 14197900028
– Programmed Serial number on FT4232H EEPROM: 141979000280B
EVM User Setup/Configuration
22
Jacinto7 J721E/DRA829/TDA4VM Evaluation Module (EVM)
SPRUIS4D – MAY 2020 – REVISED MARCH 2022
Copyright © 2022 Texas Instruments Incorporated