Rock64 Boot-up Bug with Serial Console Cable
#1
Bug 
Greetings,

The Rock64 often will not boot-up with a serial console connected to the console uart pins (6, 8, & 10).

Symptom:  lights come on, nothing happens at all.

Solution:  unplug the Tx line coming in on pin(10) prior to applying power for boot-up.




The Tx line often (if not always) has 3v3 on it when the other end is powered up, even in the idle state.  This voltage present on pin(10) of the Rock64 prevents it from booting, sadly.  I have reliably verified that unplugging the Tx line in on pin(10) of the Rock64 will allow the boot-up to start...  as it boots up , carefully plug the Tx line back onto pin(10).

Also noticed that the Tx line (if left connected to pin[10] on Rock64 power-down) will back-feed into the board, which will dimly light the red LED (small glow) !  This back-feed is preventing boot-up.

Fortunately the serial console monitor does not need this line connected to monitor as long as it has the Rx connection and a good ground,  so unplugging the line from pin(10) does not prevent monitoring the boot-up messages on the serial console.

Note:   This problem occurs on both of my boards;  dev board pre production, and the production master-piece which came last week !

Note:   At this point I don't know if the current draw on the Tx line might damage the monitor ; currently I'm using my PineA64 desk machine as the serial monitor for my Rock64 boards.


marcushh777    Cool

please join us for a chat @  irc.pine64.xyz:6667   or ssl  irc.pine64.xyz:6697

( I regret that I am not able to respond to personal messages;  let's meet on irc! )
  Reply


Messages In This Thread
Rock64 Boot-up Bug with Serial Console Cable - by MarkHaysHarris777 - 08-24-2017, 04:33 PM

Possibly Related Threads…
Thread Author Replies Views Last Post
  Are HW design files available for ROCK64? irenek 3 5,544 12-11-2023, 09:31 PM
Last Post: tllim
  Rock64 is unreliable after 3 years of service - power problem? ReleaseTheGeese 0 448 11-23-2023, 05:05 AM
Last Post: ReleaseTheGeese
  Rock64 PoE compatbility with Pi4 Hatt recent Single Board Computer offering from PINE kharak 1 1,258 04-26-2023, 11:38 PM
Last Post: tllim
  Case for the rock64 that supports the POE hat. o1CRiMSON1o 0 724 03-21-2023, 03:48 PM
Last Post: o1CRiMSON1o
Brick Rock64 usb2.0 Power Control Floating GPIO Tutorial Files & Notes MarkHaysHarris777 6 13,762 01-15-2023, 10:36 AM
Last Post: ds00
  rock64 totally brick dakobg 2 1,973 11-07-2022, 05:45 PM
Last Post: olivercfc
  3D-Printable Button Pegs for the ROCK64 Aluminium Case CounterPillow 2 3,737 08-04-2022, 01:31 AM
Last Post: Vicky Weimann PhD
  Where can I find the ROCK64 POE HAT Zoz 2 2,901 06-08-2022, 12:44 AM
Last Post: Zoz
Smile wooden case for ROCK64 killor 13 17,331 03-04-2022, 06:56 AM
Last Post: killor
  1wire DS18b20 on Rock64? mypineme 6 7,507 09-28-2021, 03:07 PM
Last Post: TRS-80

Forum Jump:


Users browsing this thread: 1 Guest(s)