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tech:rm2_otg_pogo

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tech:rm2_otg_pogo [2021/02/09 23:14]
anytimetraveler Fixed some typos and capitalisation
tech:rm2_otg_pogo [2021/02/20 17:34] (current)
tg-x
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 It is also possible to disable OTG from the pogo pins and instead use the ID pin as a UART TX. This allows the software to print logs via UART to the ID pin. This is especially useful for debugging or developing U-boot or kernel issue. It is also possible to disable OTG from the pogo pins and instead use the ID pin as a UART TX. This allows the software to print logs via UART to the ID pin. This is especially useful for debugging or developing U-boot or kernel issue.
  
-Currently this has been tested with the Linux kernel by printing the entire boot log via `uart6` which is broken out to the Pogo pin ID pin (see above). Although it should also work for u-boot.+Currently this has been tested with the Linux kernel by printing the entire boot log via `uart6` which is broken out to the pogo pin ID pin (see above). Although it should also work for u-boot.
  
 == Enable UART == == Enable UART ==
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 You should double check to make sure the args look like they originally did (without quiet) using fw_printenv mmcargs You should double check to make sure the args look like they originally did (without quiet) using fw_printenv mmcargs
  
-=== USB-in OTG mode ===+=== USB-in OTG mode ===
  
-There is a [[kernel#​otgcontrol| kernel module]] which controls the OTG mode of the USB-port, provided by remarkable.+There is a [[kernel#​otgcontrol| kernel module]] which controls the OTG mode of the USB-port, provided by remarkable.
 At present it does not correctly detect and configure when it should be an OTG host. At present it does not correctly detect and configure when it should be an OTG host.
  
-It's also possible to change the dr mode of the USB-port to OTG by executing:+It's also possible to change the dr mode of the USB-port to OTG by executing:
 <​code>​ <​code>​
-echo host > /​sys/​kernel/​debug/​ci_hdrc.1/role+echo host > /​sys/​kernel/​debug/​ci_hdrc.0/role
 </​code>​ </​code>​
  
 However, the VBUS will not be powered. However, the VBUS will not be powered.
-A powered ​usb hub does not work if the control chip still uses host vbus, which is required by the usb standard. + 
-USB-OTG forking cable might work, this has yet to be tested.+A USB-OTG forking cable does work with external power. This has been tested. 
 + 
 +A powered ​USB hub does not work if the control chip still uses host VBUS, which is required by the USB standard.
tech/rm2_otg_pogo.1612908853.txt.gz · Last modified: 2021/02/09 23:14 by anytimetraveler