Lpc2000

Thanks all.

Nic:

What you wrote caused me to wonder about the timing.  Of course, since the 
timing is controlled by the Philips Flash Utility, then how could it be 
wrong?  An inspection with a 'scope showed that it is correct - sort 
of.  What isn't right is that the two important signals RTS and DTR are 
changing state at the wrong time - ISP enable is released about 330mS 
before RESET is released.  That couldn't be right.  But I didn't bugger up 
the measurement ISP enable really is bein released before RESET.

Standard DE-9 serial pinout has DTR on pin 4 and RTS on pin 7.  Now, if you 
look at figure 2 of the Philips app note 10302 you'll see that they have 
DTR on pin 7 and RTS on pin 4.  In paragraph 3.2 they associate RTS with 
RESET and DTR with ISP Enable.  This text reference reenforces the signal 
names used in Figure 2.  So, if you design your hardware - as I did - 
following the signal nomenclature then you won't be able to program the 
controller after you've done it once.  Bloody hell.

Dropped a breakout box in the serial path, swapped DTR and RTS, and la, I 
can flash the 2106 to my hearts content.


scott

Systronix, Inc
Salt Lake City, Utah




At 21:31 2006-04-10 -0700, you wrote:
>Hi lpc2000,
>
>I have seen this question sometimes on this list. I think many users find
>the problem of the serial port programming only working for the first time
>on the user designed boards. I think this is caused by the wrong BSL or
>RESET pin timing at power on prevents the controller from going into
>bootloader mode.
>
>The controller must be in bootload mode for the serial port programming to
>work. If the BSL or RESET pin timing is wrong, an unused controller will
>still go in to bootloader mode because there is no valid user code to
>execute (this is why it works for the first time). After the first time it
>is necessary for the BSL and RESET pin timing to be correct, otherwise the
>last programmed user code is executed.
>
>Kind regards,
>
>Nic
>
>
>
>Yahoo! Groups Links
>
>
>
>