Tony, There are two ways to go regarding UL1998. First, you are required to comply with UL1998 if the failure of your microcontroller control could result in "unsafe" operation of your product (defined in narrow terms by UL). Now, if this is the case, UL will consider the control "Unreliable", and require you to test the product with the controls shorted out in various ways, effectively "failed". If you are designing a medical device, you probably are in UL1998 territory. If you are designing a consumer product, a clock, or an audio product for instance, you should specifically ask that yopur product be tested as if the control is "unreliable". That triggers a whole different set of concerns. IMHO, the PIC Flash parts that are able to read their own program memory could possibly comply with UL1998 by simply doing a checksum on their own memory. If your processor is incapable of this, you are probalby screwed unless you upgrade the processor. If your control is deemed "unreliable", you will have to show that the product does not overheat, connect the case to the mains, melt or catch on fire if the control is shorted and the product is left on and shoved up against a piece of plywood (a UL Alcove). Often people add thermal cutout fuses and other failsafe devices to pass this test. If it is a medical device, you have to show it won't zap anybody if the control is shorted out. Can you tell us in general terms what kind of product you have? Medical, consumer product, heating device, motorized product, timing device, audio device, industrial control? -- Lawrence Lile Senior Project Engineer Toastmaster, Inc. Division of Salton, Inc. 573-446-5661 voice 573-446-5676 fax Tony Pan Sent by: pic microcontroller discussion list 08/20/02 10:28 AM Please respond to pic microcontroller discussion list To: PICLIST@MITVMA.MIT.EDU cc: Subject: Re: [PIC]: What's "instruction set test"? Exactly. For UL1998. The UL engineer said he cannot tell me how to do it due to conflict of interests. That leaves me in the dark. Has anybody gone though this before? Tony ----- Original Message ----- From: "Alan B. Pearce" To: Sent: Tuesday, August 20, 2002 11:21 AM Subject: Re: [PIC]: What's "instruction set test"? > >>Can someone tell me what's instruction set test? > > >Why do you want to do this? Performing an instruction test on a single > chip > > It sounds like a requirement of safety testing labs, as has been discussed > here before in regard to queries about ROM checksums. It seems the funny > sort of test they might require. > > -- > http://www.piclist.com hint: PICList Posts must start with ONE topic: > [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads > > -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads