On Sun, 2 Apr 2023 07:31:43 +0200, Christo Crause via fpc-pascal <fpc-pascal@lists.freepascal.org> wrote:
>On Sat, Apr 1, 2023 at 9:57?PM Bo Berglund via fpc-pascal < >fpc-pascal@lists.freepascal.org> wrote: > >> Question: >> Can I use Linux file system commands to read/write the data on the i2c >> EEPROM >> memory device and if so how from fpc? >> > >To some extent it is possible to handle i2c transactions as file read/write >operations, but some ioctl calls are required to configure e.g. the device >address [1]. Take note that only a subset of i2c functionality is available >using read/write calls. Lazi2cdev [2] uses this approach. > >For finer control over the i2c transactions (for example combined >write/read transactions) low level ioctl calls are available in Linux. I >wrote an i2c class [3] using this approach. > >1. https://www.kernel.org/doc/html/latest/i2c/dev-interface.html >2. https://github.com/laz2wiringpi/lazI2cdev/blob/master/i2cdev_base.pas >2. https://github.com/ccrause/rpiplc_pas/blob/main/native/i2c.pas Thanks for the reply and links! Then I need to go the low-level way, I guess... I had hoped it would be a simpler way using OS available functions on RPi. I have used these EEPROM devices on some Microchip PIC24 projects where I had to do the nitty-gritty low level stuff myself including bit-banging the I2C bus... With that approach I have to *read the details* on the EEPROM datasheets to see how they are handled, unless of course I can port my own i2c code (Ansi-C) to pascal... Luckily on RPi the system is built to allow users to do low-level stuff on the I/O lines. -- Bo Berglund Developer in Sweden _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
