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mod-audio / cc-hw-footswitch

MOD Footswitch extension hardware repository
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protect the U4 IC when the board is being debugged #11

Closed odurc closed 9 years ago

odurc commented 9 years ago

The P1 connector provides a way to communicate directly with the uC, however when this is done the output of the U4 IC can receive current from the uart debugger, this can damage the component.

The suggestion to solve this is to use a double connector, like P2, and use jumpers to enable/disable the communication of uC with U4. In production, the header connector must not be soldered, instead of this, 0R resistors have to be used in replacement, one connecting pin 5 to 6, and other connecting pin 7 to 8. The pins 9 and 10 will not be used due the issue #4.

odurc commented 9 years ago

Going back, the pins 9 and 10 still being used, the 0R resistor already was applied to these pins in the schematic. Need to be done in the PCB.