Maxim have an app note talking about the power conditioning problem - they are selling a solution of course.
And at a substantial price.
Some careful design and a super-capacitor or CR2032 cell, along with a 512K x 8 SRAM can accomplish the same thing for about half the cost. You'd be trading time, board real estate and ingenuity for money, of course. Sequencing isn't that difficult as long as Vcc is higher than the nominal 3.0 VDC of the CR2032.
I have one HM628512 sram, i bought it for storing data from a/d converters, and for a digital analyzer project. I could use it for permanent data storage, but i would prefer other memories. If i am going to use i2c i will need a interface controller also, which raises the price... It would be great if 8BIT's SPI-IDE Interface would have a bus interface like my keyboard/lcd... pic interface...
There's an even simpler one here which treats IDE as having an 8-bit data bus - I think the idea here is that you just use half the bytes on the device - commands need only the bottom 8 bits, and for data transfers you leave the upper 8 bits alone. You won't be able to share removable media if you do this, but it is simpler.
Cheers
Ed
Edit to add: (I don't mean anything against any of the SPI-based solutions by the way. But if you happen to have old CF cards or IDE drives around, or are looking for a TTL-level solution, an IDE interface has some appeal)
Last edited by BigEd on Fri Nov 04, 2011 9:48 am, edited 1 time in total.
It's c, (a c library for FAT filesystem access) so the first step would be to have a go with cc65, I think. Then you'd need to connect it to some low-level SPI routines, or similar, if you wanted to connect to an SD or MMC card.
