Pin | Signal | Description |
1 | +5 V USB | |
2 | - Data USB (slave) | |
3 | + Data USB (slave) | |
4 | GND USB | |
5 | +5V (VDD, power out for USB Host) | |
6 | - Data USB (Host) | |
7 | USB internal / external power toggle | used with 4.7k ohm resistor & pin 15 below |
8 | + Data USB (Host) | |
9-14 | Video ?? | |
15 | USB internal / external power toggle | used with 4.7k ohm resistor & pin 7 above |
16,18 | USB GND | |
19,20,21,22 | +5 V | VCC, system power to e740 |
23,24,25,26 | GND | system power to the e740 |
Pin 7 & 15 used i.e. with the Franken-Cradle and Ultra-Cradle designs to tell the cradle to allow the e7xx to power the hub or to tell external power to power the hub. To toggle e7xx power for the USB hub (without external power) - a 4.7k ohm resistor needs to be connected between pins #7 and #15.
1st - Connect pin #7 and pin #15 with a 4.7K resistor directly on the upper connector. 2nd - use a double relay to switch both +5V and ground. As on the Franken-Cradle and Ultra-Cradle designs, the relay is driven by external power. In default position it connects USB power and ground from the PPC. For that connect pin #5 (+5V) with one relay switch defaults position. Connect ground from the PWB to the other switch in default position, its connected to the upper connector trough the flex cable with the PPC ground. If external power is connected, the switches go to connect power and ground for USB Hub directly from the external power connector.