[jakthree]

Erik,

OctavoSystems: OSD3358-SM
Toshiba: THGBMNG5D1LBAIL (JEDEC v5.0 interface)
Linux: 5.11.x

I am using GPMC_A4.RMII2_TXD1 for my second Ethernet PHY. I am considering using GPMC_CSN0.GPIO1_29 because pin P3 is next to the pins used for MMC1. The release state of GPMC_CSN0 is ‘H’. Your previous comment said the ‘H’ is a good thing. However I am confused about ‘L’ vs ‘H’.
Does ‘L’ mean active-low and ‘H’ mean active-high?
I understand that the eMMC_RSTN is active-low.
Will a ‘H’ output hold the line low keeping the EMMC in a reset condition?

You mention that  “Please note that the eMMC reset is not defined in the default device tree for either the OSD3358-SM-RED or other designs from BeagleBoard.org(TM), so you would need to define it if you would like to use that functionality.”
Can you provide an example of what to add to the device tree to define using GPIO1_29 to control eMMC_RSTN?

Thank you,

[jakthree]

Aedan,

Thank you for your detailed explanation. I understand now that PMIC_POWER_EN is an output from the RTC and that the RTC does indeed control the system power. I have left the ‘system-power-controller’ entry in my device tree.

[jakthree]

UART0 pin out in shown on sheet 3/9 the OSD3358-BAS-SBC-Ref-Design-SCH.pdf.

Where in the OSD335x Reference Design Tutorial Series is the UART0 pin out mentioned?

Thank you,

[jakthree]

I looked at the OSD3358-BAS-SBC-Ref-Design-SCH.pdf and  OSD3358-SM-RED_Platform_sch.pdf. Both have a 100K resistor connecting Sn74LVC2G241 pin-2 (B_UART0_RX) to GND. I tried same on one of my custom board and it seems to have fixed the ‘receiving characters when nothing connected’ problem. I will try same on multiple boards.

Thank you

 

[jakthree]

This is a custom board based on the Beagle Bone Black. The BBB has a 6-pin header for console output via connecting a USB to 3.3v TTL cable. UART0_TX and UART0_RX from the OSD3358 are connected to the 6-pin header through a SN74LVC2G241DCUR chip. I can’t find anywhere in the Octavo app notes where the UART0 is used as a console port. The BBB has a 100k ohm resistor connected to pin-2 (B_UARTo_RX) to ground.

Do you recommend the same?

Thank you,

[jakthree]

I have found that the MDIO_CLK, MDIO_DATA, address/mode straps and power to the PHY(s) is all that are needed for successful MDIO communications. You also need the correct external pullup resistor value for the MDIO_DATA line. The OSD3358 REFCLK is only used to synchronize the RMII signals.

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