----- Original Message ----- From: "RussellMc" To: "Microcontroller discussion list - Public." Sent: Saturday, June 26, 2010 9:57 AM Subject: Re: [EE] Slew Rate Limited Clock Buffer? After one of these strings takes on a life of its own, the original message and much of the information in the replies becomes easier to forget/overlook. Since I have only an academic interest and not enough knowledge to help Harold with this problem, I have had the luxury of being able to take the time to follow the conversation without getting lost. So, please take the below in the spirit in which it is offered. Russell wrote, "This is [EE] and no PIC was mentioned by Harold so it may very well that its not a PIC that's used." Harold's 6/25 post stated, "We have a 33 ohm series resistor between the PIC32 pin and the trace." Oli wrote, " thought the 75Mhz was the top speed the flash recipients mentioned could go to, but I haven't seen any mention of the *actual* clock speed being used. " and Russell responded, "75 MHz clocking capability WAS noted, but it's not necessarily what drives the worst case result." Harold's original post stated, "Part way down the trace are three SPI flash chips that can run at 75MHz." So, true, we still don't have a clue about at what speed the PIC32 SPI bus is being run, only the speed at which the peripheral SPI chips CAN operate. Though several folks have offered suggestions, isn't it possible that the missing information may be relevant to the real solution, if for no other reason than to eliminate the PIC32 SPI speed as a contributing factor? Other info that may help is PIC32 and SPI flash device part numbers and forms. Someone may have encounterd manufacturer errata for these devices that may also be relevant to the problem Harold is experiencing. Okay, that's enough thinking for this morning. Richard -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist