Messages

Hi Andy,

yes, I tried another device and the behaviour was the same. But I found out something:
In my application I have a power fail circuit that uses the external interrupt 1. If this becomes active some parameters will be saved into the internal flash memory and normally after that the system dies. But for some reasons (when there only was a dropout for examle, or for testing) I use the watchdog to active shut down the whole system (same as when power was lost).

Now I take an completely erased hardware and the ISP FlashMagic tool works fine until I use this watchdog for the first time, after that I can't enter the boot loader mode again. Also after disconnecting the power for some minutes It's not possible to read the device ID.
The only way is to short the EINT0 pin for some seconds and then to short the reset pin. (that is exactly what the FlashMagic tool does, but there must be a difference I didn't see yet). At this time the flash holds the application program and FlashMagic is able to read the device ID for example.
It seems like the boot loader sees the watchdog flag and a valid application and starts the application.
Spooky, a reset doesn't clear this watchdog flag.
If I know more, I will tell you, it's an amazing problem.

Kuno

Hi Andy,
I did what you said: The device seems not to be in ISP mode in error case.
But I can't see any difference when the system works except that the LPC2378 is responding when all runs well. The IEINT0 and RESET behaviour is identical in both cases.
This is very spooky, It seems to be a difference if the system powers up or only the RESET was active with all voltages already present. The POR (power on reset) seems to have some impact.

Hi Andy,

yes, the DTR/RTS option  is enabled. Also I monitored the TTL signals directly on the chip and didn't find strange things. FlashMagic applies the reset for some time while IEINT0 pin is set low, after T2 the communication starts, but in error case the chip gives no answer. When I had luck and the system runs the signals look like in error case but the chip will answer to FlashMagic tool. At this point all runs well.

So, now I will leave to the weekend, thanks an enyoy your weekend too.  Kuno

Hi Andy, thanks for your statement.
The IENIT0 Pin of the LPC2378 (that is used to set the device into ISP mode) is driven by RTS and IRESET is driven by DTR signals done with 2 transistors; I found this in the MCB2300 eval board drawings and made the same in my design. The bootloader version of LPC2378 is V3.2.
This morning when I powered up the whole stuff, I could read the device ID but minutes later the chip didn't respond again. Sometime it was possible to communicate and program the device, but I didn't find out what's wrong.

Hi,

I use FlashMagic 4.17.273; Target: LPC2378 chip; OSC = 12MHz;

When the Flash is cleared (done with the ULINK debugger) then it's no problem to enter ISP mode with Flashmagic to program the LPC2378.
But once programmed it's not possible to enter ISP mode again.
For example: to read the device ID FlashMagic says "operation failed to autobaud, step1". Osc shows that the chip isn't responding any more.

The code read protection location at 1FC is disabled (set to FFFFFFFF) in the programmed application.

I tryed to set OSC to 14.748 or 12Mhz, lowered the baudrate, increased the times T1 and T2 but no result until now. If someone knows what I'm doing wrong it would be great to know.
                                      Kuno