.\"	$NetBSD: seeprom.4,v 1.6 2013/10/25 22:15:02 wiz Exp $
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.Dd October 25, 2013
.Dt SEEPROM 4
.Os
.Sh NAME
.Nm seeprom
.Nd 24-series I2C EEPROM driver
.Sh SYNOPSIS
.Cd "seeprom0 at iic0 addr 0x51: AT24Cxx or compatible EEPROM: size 256"
.Cd "seeprom16 at iic1 addr 0x57: power-supply: size 8192"
.Sh DESCRIPTION
The
.Nm
driver provides support for the ATMEL 24-series of I2C EEPROMs, and
compatibles, available from a variety of vendors.
The Philips PCF8582 is also supported, as compatible with the
AT24C02.
.Pp
Access to the contents of the memory is through a character device.
.Pp
The size of the EEPROM is either read from the firmware, or can be set
using the flags keyword in the kernel configuration.
The value of the flag represents the EEPROM size in Kbit.
.Bl -column -offset indent "flags" "EEPROM size in bytes"
.It Sy flags Ta Sy EEPROM size in bytes
.It Li 1 Ta 128
.It Li 2 Ta 256
.It Li 4 Ta 512
.It Li 8 Ta 1024
.It Li 16 Ta 2048
.It Li 32 Ta 4096
.It Li 64 Ta 8192
.It Li 128 Ta 16384
.It Li 256 Ta 32768
.It Li 512 Ta 65536
.El
.Sh EXAMPLES
Indirect configuration:
.Dl seeprom* at iic? addr 0x51 flags 0x2
Direct configuration:
.Dl seeprom* at iic? addr?
.Sh SEE ALSO
.Xr iic 4
.Sh HISTORY
The
.Nm
device appeared in
.Nx 2.0 .
.Sh BUGS
AT24C1024 EEPROM's are not supported.
.Pp
Software write protection on the AT34Cxx EEPROMs is not supported.
.Pp
The
.Nm
driver reads and writes one byte at a time to be compatible with all
controllers.