Difference between revisions of "USB"

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{| border="1" cellpadding="5" cellspacing="0"
 
{| border="1" cellpadding="5" cellspacing="0"
 
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|-
| style="width:100px;background:green;" | USBH_PWR1 || colspan="2" | Pull-up to 3.3 volts to enable USB port
+
| style="width:100px;background:limegreen;" | USBH_PWR1 || colspan="2" | Pull-up to 3.3 volts to enable USB port
 
|-
 
|-
| style="background:green;" | USBH_PEN1 || colspan="2" |
+
| style="background:limegreen;" | USBH_PEN1 || colspan="2" |
 
|-
 
|-
| style="background:green;" | USBH_P1 || rowspan="4" align="center" | USB port || USB D+
+
| style="background:limegreen;" | USBH_P1 || rowspan="4" align="center" | USB port || USB D+
 
|-
 
|-
| style="background:green;" | USBH_N1 || USB D-
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| style="background:limegreen;" | USBH_N1 || USB D-
 
|-
 
|-
 
| style="background:tomato;" | V_BATT || USB VBUS
 
| style="background:tomato;" | V_BATT || USB VBUS

Revision as of 11:02, 14 March 2008

USBH_PWR1 Pull-up to 3.3 volts to enable USB port
USBH_PEN1
USBH_P1 USB port USB D+
USBH_N1 USB D-
V_BATT USB VBUS
GND USB DGND


The 24-pin flex ribbon connector has USB port 1 on it. The pinouts you need are:


  • V_BATT (pin 24) - USB power
  • USBH_N1 (pin 18) - USB D-
  • USBH_P1 (pin 17) - USB D+
  • GND (pin 8) - USB Ground


In addition, you need to pull USBH_PWR1 (pin 20) up to 3.3 volts to enable the port. You need to provide a stable 3.3 volt supply, which is fairly simple to do by adding a small SOT23 package voltage regulator (like the LM3480), with the power input coming from V_BATT (pin 24) and the output going to USBH_PWR1 (pin 20).