General
Review and verify the following for the custom
board schematic design:
- The recommendation is to add provision to isolate the IOs that can be used for
debug from alternate functions
- The recommendation is to add provision for connecting UART0 interfaces for debug
during initial board build
- The recommendation is to add provision for pulls for the UART interface signals
that can float
- The recommendation is to add provision for JTAG connector or Test points for
JTAG interface signals
- The recommendation is to place the pulls for the JTAG interface signals and
EMU0, EMU1 as per pin connectivity requirements near to the processor JTAG
interface pins
- The recommendation is to add provision for external ESD protection for the UART
and JTAG interface signals
Schematic Review
Follow the below list for the custom schematic design:
- Provision to connect the debug UARTs have been provided (UART0, WKUP_UART0)
- 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
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 AM62Lx processor family.