<section begin="History" />
{| style="border-collapse:collapse; "
!colspan="4" style="width:100%; text-align:left"; border-bottom:solid 2px #ededed"|History
|-
!style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#73B2C7; padding:5px; color:white"|Version!style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#73B2C7; padding:5px; color:white"|Issue Date!style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#73B2C7; padding:5px; color:white"|Notes
|-
|style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#edf8fb; padding:5px; color:#000000"|X.Y.Z2021/01/14|style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#edf8fb; padding:5px; color:#000000"|Month Year|style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#edf8fb; padding:5px; color:#000000"|TBDFirst Release
|-
|-
|style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#edf8fb; padding:5px; color:#000000"|[TBD_link X.Y.Z]
|style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#edf8fb; padding:5px; color:#000000"|Month Year
|style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#edf8fb; padding:5px; color:#000000"|TBD
|-
|style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#edf8fb; padding:5px; color:#000000"|...
|style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#edf8fb; padding:5px; color:#000000"|...
|style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#edf8fb; padding:5px; color:#000000"|...
|-
|}
<section end="History" /><section begin="Body" /> ==USB ports == === Description ===ETRA SBC provides two USB ports, one HOST and one OTG:* J17 is a standard USB HOST 2.0 Type A connector
==USB interface ==
''TBD[[File: sostituire le sezioni con le informazioni sull'uso della periferica e del suo connettore''''Nell'esempio di seguito c'è la descrizione dell'interfaccia UART/console''ETRA-EVK-USB-HOST-connector.png|thumb|center|300px|USB HOST connector]]
=== Description ===
The * J16 is a micro-AB type receptacle for a USB OTG connection: this interface available on the Evaluation Kit at the connector ''TBD:Jxxx''. can operate in Host mode and Device (peripheral) mode
''Jxx'' is a ''TBD:connector-type'' header connector for the RS232 two-wires UART3 port, used for debug purposes (bootloader and operating system serial console).
[[File:ETRA-EVK-USB-OTG-connector.png|thumb|center|300px|USB connector]]
[[File:{{{nome-som}}-EVB-USB-connector.png|thumb|center|500px|USB connector]]
===Signals ===
The following table describes the interface signals:
==== USB HOST ===={| class="wikitable" ! latexfontsize="scriptsize"| Pin#! latexfontsize="scriptsize"| SOM Pin#! latexfontsize="scriptsize"| Pin name! latexfontsize="scriptsize"| Pin function! latexfontsize="scriptsize"| Pin Notes|-|1|J18.188|USB_HOST_VBUS|VBUS||-|2|J18.202|USB_DM1|USB Host Data -||-|3|J18.200|USB_DP1|USB Host Data +||-|4| -|DGND|Ground|
|-
|1,2,45,6,,7,8,10
| -
| NPCB_GND_RNG|Shield||} ==== USB OTG ===={| class="wikitable"!Pin#!SOM Pin#!Pin name!Pin function!Pin Notes|-|1|J18.A185|VBUS_OTG_IN|VBUS|Can be used to power the board|-|2|J18.196|USB_DM2|USB OTG Data -||-|3| N.CJ18.198|USB_DP2|USB OTG Data +| Not connected
|-
| 34| J1J18.18972| RS232_RXPA8| Receive lineUSB OTG ID|
|-
| 35| J1.187-| RS232_TXGND| Transmit lineGround|
|-
| 96, 7, 8
| -
| DGNDPCB_GND_RNG| GroundShield|
|}
=== Device mapping ===
UART3 is mapped to <code>/dev/ttymxc2</code> device in Linux. The peripheral is USB Host port can be used as the default serial console, both under Linux for connecting USB peripheral devices: the bootloader and related peripheral driver has to be integrated into the Linux kernel. === Device usage === To connect to the debug serial port: # connect the DB9 adapter bracket to the J22 connector on the SBCX board# connect a serial cable between DB9 connector and PC COM port through a NULL-modem cable (not provided)# start your favorite terminal emulator software on PC (eg: PuTTY); communication parameters are: 115200,N,8,1
The USB OTG feature can be easily tested using the Mass Storage Gadget driver.
----
[[Category:ETRA]]