ZHCSIR7N March 2009 – September 2018 MSP430F5513 , MSP430F5514 , MSP430F5515 , MSP430F5517 , MSP430F5519 , MSP430F5521 , MSP430F5522 , MSP430F5524 , MSP430F5525 , MSP430F5526 , MSP430F5527 , MSP430F5528 , MSP430F5529
All devices come preprogrammed with the USB BSL. Table 6-3 lists the required pins for the USB BSL. In addition to these pins, the application must support external components necessary for normal USB operation; for example, the proper crystal on XT2IN and XT2OUT, proper decoupling, and so on.
|DEVICE SIGNAL||BSL FUNCTION|
|PU.0/DP||USB data terminal DP|
|PU.1/DM||USB data terminal DM|
|PUR||USB pullup resistor terminal|
|VBUS||USB bus power supply|
|VSSU||USB ground supply|
The default USB BSL evaluates the logic level of the PUR pin after a BOR reset. If the PUR pin is pulled high externally, then the BSL is invoked. Therefore, unless the application is invoking the BSL, it is important to keep PUR pulled low after a BOR reset, even if BSL or USB is never used. TI recommends applying a 1-MΩ resistor to ground.