jnz4 Forth F-RAM driver
there are a lot of intersting things in Jeelabs.org page and this forum.
That's is my less than a contribute but just experience for sharing.
I soldered a Cypress FM25CL64 F-RAM chip on HyTiny Extender and i write an ugly Forth driver.
It's a very cool mem. No pagination, no delay. Moreover High-endurance 100 trillion (10
14) read/writes. I did it thinking to counter datalogger applications.
Take a look to http://www.cypress.com/file/41676/download
If anyone is interested in writing a driver this is a useless photo and some code.
\ already included in tex/board.fs PA15 constant SMEM.SEL \ SPI flash memory CS usef for F-RAM SMEM.SEL ssel ! \ change definition in spi.fs for Slave Select spi-init \ F-RAM DRIVER $06 constant FR:WREN \ set write enable latch $05 constant FR:RDSR \ read status register $04 constant FR:WRDI \ write disable $03 constant FR:READ \ read memory data $02 constant FR:WRITE \ write memory data $01 constant FR:WRSR \ write status register : frmem-cmd ( cmd -- ) +spi >spi ; : frmem-rdsr ( -- rdsr ) +spi FR:RDSR >spi spi> -spi . ; : frmem-wren ( -- ) FR:WREN frmem-cmd -spi ; \ set write enable latch : frmem-read8 ( addr -- c ) dup $FF and swap 8 rshift $FF and \ address 13 bit in two byte conversion (MSB first) FR:READ frmem-cmd >spi >spi spi> -spi . ; : frmem-read32 ( addr -- u ) dup $FF and swap 8 rshift $FF and \ address 13 bit in two byte conversion (MSB first) FR:READ frmem-cmd >spi >spi 0 4 0 do 8 lshift spi> or loop -spi . ; : frmem-write8 ( addr c -- ) frmem-wren swap dup $FF and swap 8 rshift $FF and \ address 13 bit in two byte conversion (MSB first) FR:WRITE frmem-cmd >spi >spi >spi -spi ; : frmem-write32 ( addr u -- ) dup $FF and swap 3 0 do 8 rshift dup $FF and swap loop drop \ prepare stack to transmit MSB at first 4 pick dup $FF and swap 8 rshift $FF and \ address 13 bit in two byte conversion (MSB first) frmem-wren FR:WRITE frmem-cmd >spi >spi \ write address 4 0 do >spi loop -spi drop ;
RE: jnz4 Forth F-RAM driver - Added by jcw about 1 month ago
Very nice - thanks for sharing!
Interesting chip - I see they're available in sizes from 512 to 512K bytes, and there's even a DIP-8 version.