Making best use of EEPROM Page Memory

[Dave]

Tom, I beg to differ. The page size of the 24LC512 is 64 bytes. I know this as I have been using it for logging depth and temperature of a towable apparatus used for fishing.

Dave Purola,
N8NTA

[Tom Gonser]

Hmm.. Mine fail at 64b page writes, and a review of the data sheet it clearly says 128. The 24LC51*5* is 64by pagewrite... but it also needs to switch address blocks at 256kbits (upper and lower). the 512 is one block of bits.

TG

So nobody has invented a better scheme of using EEPROM pages... ack. Has anyone used Compact Flash with PB Pro then? I see the Proton+ development environment supports CF commands but I don't know about PBP...

[Archilochus]

Has anyone used Compact Flash with PB Pro then? I see the Proton+ development environment supports CF commands but I don't know about PBP...

Hi Tom,
Check here for PicBASIC code to write/read MMC / SD cards. The 'free' software version does not handle FAT formatting of the cards for use with Windows.

http://www.compsys1.com/workbench/On...c_project.html

Arch

[Tom Gonser]

Thanks for the pointer. I assume with this kind of setup, the strategy is to write 512bytes or so to EEPROM, (in my case 14.2 records) actually 14 records, and I guess nothing goes in the last '.2'.. (also what happens when I read it back? Does the extra unused space show up in read data as $ffff or something?)

Then, a routine writes from EEPROM to the SD card. Then we'd increment the sector on the SD card and keep going?

I see that there is code available to write to FAT 16 formatted cards also - for my project this would be a big benefit. However, I don't know much about the SD formats, etc.

1. Are SD cards pre-formatted as Fat16?
2. If it is not formatted as FAT16, is there ANY way to read the data from a PC?
3. What does 'write only one file' mean? I assume just a contigous block of incrementing addresses?

Why does one use SHIFTIN or SHIFTOUT?? Is it for SPI mode?

Tom

[Dave]

Tom, I'm sorry, you are right. I must have been having a serior moment..... I am using the 24LC515.... Oh well, Next time I'll keep my mouth shut......

Dave Purola,
N8NTA