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| USB 2.0 |
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| Datasheet |
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BIT |
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NUMBER | BIT NAME |
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3:2 | BOOST_IOUT_2 | USB electrical signaling drive strength Boost Bit for Downstream Port ‘2’. | |
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| ‘00’ = Normal electrical drive strength = No boost | |
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| ‘01’ = Elevated electrical drive strength = Low (approximately 4% boost) | |
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| ‘10’ = Elevated electrical drive strength = Medium (approximately 8% boost) | |
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| ‘11’ = Elevated electrical drive strength = High (approximately 12% boost) | |
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| Note: | “Boost” could result in |
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| example would be Test J/K levels), the OEM should use a 00 value |
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| unless specific implementation issues require additional signal |
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| boosting to correct for degraded USB signalling levels. |
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1:0 | BOOST_IOUT_1 | USB electrical signaling drive strength Boost Bit for Downstream Port ‘1’. | |
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| ‘00’ = Normal electrical drive strength = No boost | |
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| ‘01’ = Elevated electrical drive strength = Low (approximately 4% boost) | |
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| ‘10’ = Elevated electrical drive strength = Medium (approximately 8% boost) | |
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| ‘11’ = Elevated electrical drive strength = High (approximately 12% boost) | |
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| Note: | “Boost” could result in |
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| example would be Test J/K levels), the OEM should use a 00 value |
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| unless specific implementation issues require additional signal |
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| boosting to correct for degraded USB signalling levels. |
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4.2.1.20Register FAh: Port Swap
BIT |
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NUMBER | BIT NAME | DESCRIPTION |
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7:0 | PRTSP | Port Swap: Swaps the Upstream and Downstream USB DP and DM Pins for |
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| ease of board routing to devices and connectors. |
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| ‘0’ = USB D+ functionality is associated with the DP pin and D- functionality |
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| is associated with the DM pin. |
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| ‘1’ = USB D+ functionality is associated with the DM pin and D- functionality |
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| is associated with the DP pin. |
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| Bit 7= Reserved |
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| Bit 6= Reserved |
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| Bit 5= Reserved |
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| Bit 4= Reserved |
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| Bit 3= Reserved |
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| Bit 2= ‘1’; Port 2 DP/DM is Swapped. |
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| Bit 1= ‘1’: Port 1 DP/DM is Swapped. |
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| Bit 0= ‘1’:Upstream Port DP/DM is Swapped |
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Revision 1.96 | 22 | SMSC USB2512A |
| DATASHEET |
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