General
Review and verify the following for
the custom board schematic design:
- Provision for isolating the circuit sections.
- Provision to external debug interface.
Schematic Review
Follow the below list for the custom
schematic design:
- The recommendation is to add provision to isolate the IOs that can be used
for debug from alternate function.
- Provision to connect the debug UARTs have been provided (UART0, MCU_UART0,
WKUP_UART0). The recommendation is to add provision for connecting UART
interfaces for debug during initial board build.
- The recommendation is to add provision for JTAG connector or Test points for
JTAG interface signals. The recommendation is to place the pulls as per pin
connectivity requirements near to the processor JTAG interface pins.
- The required pullup and
series resistors are provided for the UART interface signals.
- External ESD protection provision added when external interface signals are
directly connected to the processor UART signals. The recommendation is to
add provision for external ESD protection for the JTAG interface
signals.
Additional
- A number of processor IOs
including UARTs are not fail-safe. The recommendation is to connect external
inputs only after the processor supplies ramps
- The recommendation is to
disconnect the external interface signals in case the processor board is powered
off
Refer below FAQ:
[FAQ] SK-AM62: Purpose Of Different
UARTs
The FAQ is generic and can also be used for AM62A7, AM62A7-Q1, AM62A3, AM62A3-Q1,
AM62A1-Q1 and AM62D-Q1 processor families.