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I had a need to force the (near) equivalent of a hardware reset on the SuperPro. It doesn't directly support it by any means except a few of the interrupts. With a bit of niggling, I got this to work. Addresses might change on other NXP chips. I'm using the standard BASICTools poke equivalents.

Lloyd

#define WDMOD *&H40000000 ' watchdog mode register
#define WDFEED *&H40000008 ' watchdog timer feed register, must get an "AA" followed by a "55" to work
#define WDTC *&H40000004 ' watchdog timer timeout constant register
.
.
.
interrupt(0) ' turn off interrupts, so my local IRQs cannot interrupt our settings of the Watchdog timer
WDTC = &H000000FF ' set the time constant to the minimum
WDMOD = &H00000003 ' set the WDMOD register to enable interrupts and start the watchdog with WDEN and WDRESET true
WDFEED = &H000000AA ' poke the Watchdog timer feed register with the start of a feed command
WDFEED = &H00000055 ' finish the feed command. At LEAST ONE successful feed must occur to assert WDRESET
WDFEED = &H000000AA ' now start another feed, but this time,
WDTC = &H00000000 ' cause a fault interrupt by not completing it properly with a 0x55
interrupt(1) ' just on GPs to keep things balanced, not that it will have any effect, since a reset is occurring

just a quick thot : there is no EINT available??

olzeke51
update - didn't see any on the Schematic !!! just the reset from the dongle and a switch

I didn't have any i/o pins available to assert an external interrupt, even if it supported it. I could have always hard-wired it on the board.

But I like being able to force it from (purely) software. As Bruce demonstrated in another thread, just jumping to the boot ROM start didn't accomplish a 'full' reset. This appears to work just fine. User code cranks up without any other intervention.

http://www.coridiumcorp.com/forum/viewt ... hdog#p2283

Lloyd
(PS... I'm going to re-post this in that thread, also, since it seems applicable)

BTW... it turns out that Bruce already defined all those registers for us.

Here are the defs from LPC17xx.bas (from BASICLIB)

#define WDG_BASE_ADDR &H40000000
#define WD_WDMOD *(WDG_BASE_ADDR + &H00)
#define WD_WDTC *(WDG_BASE_ADDR + &H04)
#define WD_WDFEED *(WDG_BASE_ADDR + &H08)
#define WD_WDTV *(WDG_BASE_ADDR + &H0C)
#define WD_WDCLKSEL *(WDG_BASE_ADDR + &H10)

Lloyd