Utilisateur:Cyprien

FTDI Basic auto-reset for LPC

LPC micro-controlers can be programmed using the standard serial line using the ISP mode. This requires to have the ISP pin grounded when the LPC goes out of reset. It's often done using two micro-switches you have to manually press and release in the correct order.

How does it work?

• When the DTR signal goes up, the Reset is pulled down, putting the LPC into reset. At this moment C1 starts to discharge through R3, and if DTR is asserted long enough, the ISP pin is put low too.
• When DTR is back to normal, the LPC goes out of Reset, and if C1 is discharged enough enters ISP mode.