J-Mem is a small stand-alone application for Microsoft Windows (Windows 2000 and later). It requires a J-Link connected to the USB port and an ARM system connected to J-Link via the JTAG interface. J-Mem makes it possible to look into the memory of an ARM chip at run-time; RAM can be modified and Special Function Registers (SFRs) can be written. The type of access for both read and write access can be selected to be 8/16/32 bit. It works nicely when modifying SFRs, especially because it writes the SFR only after the complete value has been entered.
J-Mem is distributed as part of the J-Link software and documentation package and can be used free of charge.