topic K64f help adding external RAM in Kinetis Microcontrollers

K64f help adding external RAM

unknowncoder — Wed, 28 Feb 2018 15:45:46 GMT

Hello,

We need to add at least 1Megabyte of RAM to the MK64FN1M0VLL12.

From my understanding we need to use the FlexBus to do this? Which has address space 0x6000_0000–0xDFFF_FFFF. With a totoal size of 512MB.

I don't fully undetstand what the FlexRAM is used for (0x1400_0000–0x17FF_FFFF )? If we could use this it would be much easier.

Can someone provide some help on how to add external RAM?

Thanks

Re: K64f help adding external RAM

davidsherman — Wed, 28 Feb 2018 20:21:54 GMT

FlexRAM can be used as RAM, but it is only 4KB in size. It is primarily used for programming the flash memory sectors in the FlexNV section. The FlexBus brings out bus control signals (address/data bits, read/write, chip selects, byte enables) so you could connect a suitable parallel SRAM. Bear in mind depending on the type and data width of the RAM you may be using several of the available pins for address pins to get to 1MB. For that size I'm thinking the Flexbus will need to be multiplexed, so you will also need an address latch in addition to the SRAM.

Re: K64f help adding external RAM

unknowncoder — Mon, 05 Mar 2018 19:03:27 GMT

I have sourced the following RAM

IS61WV25616EDBLL-10TLI ISSI, Integrated Silicon Solution Inc | Integrated Circuits (ICs) | DigiKey

Can someone comment on compatibility it looks like it can work just fine.