Difference between revisions of "PineNote"

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This decision requires the PineNote motherboard to be able to detect an AND condition between CC1 and CC2 and connect one of the SOC's UARTs to pins on the USB-C connector. In all other cases, the UART should be disconnected. It also requires the PINE64 Store ship a simple one-sided (no magical flipping here, sorry) connector board which breaks out USB 2.0 and UART.

There were concerns that cheap USB-C cables have both CC1 and CC2 shorted together to save a wire. There is an additional concern (not in the IRC logs) that only checking for CC1 and CC2 being pulled high is not technically within USB-C DAM specifications, since detecting CC1 and CC2 being pulled high ''or'' low is mentioned.

There were concerns that cheap USB-C cables have both CC1 and CC2 shorted together to save a wire.

Detecting a pull-up condition is all that is required, as according to the USB-C spec, 'B.2.4.1.5.1 ("UnattachedDeb.SRC Requirements"), a Debug and Test System (DTS) that is a power source must pull CC1/CC2 up, while the Target System (TS) in Unattached.SNK is supposed to pull them low.' In English, this means that we'd only need to detect a pull-up condition on CC1 and CC2, meaning a logical AND between them is a sane solution. <del>There is an additional concern (not in the IRC logs) that only checking for CC1 and CC2 being pulled high is not technically within USB-C DAM specifications, since detecting CC1 and CC2 being pulled high ''or'' low is mentioned.<del>

IRC logs of this discussion can be found at [[PineNote/Debug_Accessory_Mode_Discussion]].

@@ Line 136: / Line 136: @@
 This decision requires the PineNote motherboard to be able to detect an AND condition between CC1 and CC2 and connect one of the SOC's UARTs to pins on the USB-C connector. In all other cases, the UART should be disconnected. It also requires the PINE64 Store ship a simple one-sided (no magical flipping here, sorry) connector board which breaks out USB 2.0 and UART.
-There were concerns that cheap USB-C cables have both CC1 and CC2 shorted together to save a wire. There is an additional concern (not in the IRC logs) that only checking for CC1 and CC2 being pulled high is not technically within USB-C DAM specifications, since detecting CC1 and CC2 being pulled high ''or'' low is mentioned.
+There were concerns that cheap USB-C cables have both CC1 and CC2 shorted together to save a wire.
+Detecting a pull-up condition is all that is required, as according to the USB-C spec, 'B.2.4.1.5.1 ("UnattachedDeb.SRC Requirements"), a Debug and Test System (DTS) that is a power source must pull CC1/CC2 up, while the Target System (TS) in Unattached.SNK is supposed to pull them low.' In English, this means that we'd only need to detect a pull-up condition on CC1 and CC2, meaning a logical AND between them is a sane solution. <del>There is an additional concern (not in the IRC logs) that only checking for CC1 and CC2 being pulled high is not technically within USB-C DAM specifications, since detecting CC1 and CC2 being pulled high ''or'' low is mentioned.<del>
 IRC logs of this discussion can be found at [[PineNote/Debug_Accessory_Mode_Discussion]].

Difference between revisions of "PineNote"

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