Log in to follow, share, and participate in this community. The IO pin will be 5V tolerant if the supply voltage Vdd is present, and they are configured as inputs. VDDIO must be applied to the microcontroller when input voltage is 5V, or else the 5V tolerance does not apply. &... To place code in RAM, follow the link here: http://support.code-red-tech.com/CodeRedWiki/CodeInRam The following formula may be used to calculate a parallel resonant crystal's external load capacitors: CL = ((CX1 x CX2) / (CX1 + CX2)) + Cstray where: CL = the crystal load capacitance Cstray = the stray capacitance ... Yes. In case of a software reset like WD reset, BOD reset etc, the SRAM contents (memory address 0x1000 0000 to 0x1000 2000 in case of LPC1227 ) is retained. However, the part won't retain the contents if it goes to d... The LPCXpresso IDE is available for Windows, Linux and Mac OS X hosts. LPCXpresso can be downloaded from here.