Difference between revisions of "USB"

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The [[24pin_connector|24-pin flex ribbon]] connector has USB port 1 on it. USB port 2 is on the [[60pin_connector|60-pin Hirose connector]]  
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The [[24pin_connector|24-pin flex ribbon]] connector has '''USB port 1''' on it. '''USB port 2''' is on the [[60pin_connector|60-pin Hirose connector]]  
  
 
The pinouts you need for USB port 1 are:
 
The pinouts you need for USB port 1 are:
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C1,C2: 0.1uF
 
C1,C2: 0.1uF
  
(read warning above)
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(*read warning above)
  
  
 
== Related ==
 
== Related ==
  
 +
 +
[http://pubs.gumstix.com/documents/PXA%20Documentation/PXA270/PXA270%20Design%20Guide%20%5b280001-002%5d.pdf PXA270 Design Guide, P. 202]
  
 
[http://www.usb.org/developers/docs/usb_20_092407.zip Universal Serial Bus Revision 2.0 specification]
 
[http://www.usb.org/developers/docs/usb_20_092407.zip Universal Serial Bus Revision 2.0 specification]
  
 
[ftp://ftp.compaq.com/pub/supportinformation/papers/hcir1_0a.pdf Open HCI—Open Host controller Specification for USB]
 
[ftp://ftp.compaq.com/pub/supportinformation/papers/hcir1_0a.pdf Open HCI—Open Host controller Specification for USB]
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[http://www.fairchildsemi.com/an/AN/AN-5052.pdf Implementing the Physical Layer in a USB 2.0 Compliant System, AN-5052, Fairchild Semiconductor]
  
  

Revision as of 15:01, 4 April 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. USB port 2 is on the 60-pin Hirose connector

The pinouts you need for USB port 1 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).


WARNING: This information could be yet inaccurate. TODO: D+/D- pull-down resistors (software?), termination resistors and capacitors for EMI suppresion, plus USBH_PEN1 and USBH_PWR1


Examples

File:24-pin-usb-example.png

U1: LM3480

C1,C2: 0.1uF

(*read warning above)


Related

PXA270 Design Guide, P. 202

Universal Serial Bus Revision 2.0 specification

Open HCI—Open Host controller Specification for USB

Implementing the Physical Layer in a USB 2.0 Compliant System, AN-5052, Fairchild Semiconductor


.