Content originally posted in LPCWare by idol on Fri Mar 01 02:30:31 MST 2013 when we connect the isp of lpcxpresso LPC812, We must pay attention to R55 that is connected to AD. We must put the resistance welding down,or we cannot connect the isp
Content originally posted in LPCWare by TheShed on Fri Mar 01 04:45:08 MST 2013 Not a great piece of design is it....
With the trimming pot wound all the way up the external uart can never pull ISP-RX below half rail. In my setup it doesn't get much below 1.9V which is well outside the limit for a valid LOW of 0.3VDD. On the plus side, it is a 22k pot so set it to anywhere *except* against the end stop and it should be fine.
I think this highlights the one flaw I have found so far with the LPC8xx design: The two analogue compare inputs are both assigned to ISP pins. One would have been OK but not both.
Could I request that this is changed for the next part in the family - please...
