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--- fixed_bor_setup [2006/02/06 22:46] – smashtv
+++ fixed_bor_setup [2006/10/15 09:35] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
+LCD Message "fixed BOR setup"
+  * **//From the forum://**
+The BOR feature is a brown-out reset, which resets the core if Vdd is too low.
+  * **//From the Change Log://**
+The "Brown Out Reset" (BOR) settings in the configuration sector are changed automatically when MIOS detects unproper settings - the appr. cell in this sector will be overwritten and the device will be reset.
+New Setting: Brown Out Reset at 4.5V
+This ensures that the PIC won't access devices during power-off which cannot operate at voltages < 4.5V (e.g. the [[Bankstick]], which could get an unintended write command)
+  * **//From the forum: //**
+The LCD message you saw notifies about the activation of the BOR flag, see documentation in the Change Log: http://www.ucapps.de/mios_changelog.html - this is no error message, but just a hint, that this (required!) change has been done.
+So, what could happen: your PSU is too weak, or there is a short circuit somewhere, which drops the core   voltage to below 4.5V. At this voltage some external components (like LCDs or [[bankstick]]s) don't work   reliable anymore, therefore the PIC is forced into reset state, so that nothing "dangerous" happens (e.g. so that the [[bankstick]] format routine won't be started). Probably for your application the BOR reset is not really relevant, but in general it makes sense to activate it.
+So - my tip - remove all 74HC595 chips and check if the reset still happens. The successively put them into the sockets again (switch-off the power when doing this!) in order to find out, which part of the DOUT chain is defective. \\
+If this doesn't help, disconnect the whole DOUT chain from the core module in order to find out, if the short-circuit is there, or anywhere else.
+Best Regards, Thorsten.