From 559eb9b470ebdb5c4aeafac8843882db387da61e Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Tue, 22 Jul 2003 15:33:54 +0000 Subject: [PATCH] Saa1064 module documentation, written by Sascha Volkenandt. git-svn-id: http://lm-sensors.org/svn/lm-sensors/trunk@1898 7894878c-1315-0410-8ee3-d5d059ff63e0 --- doc/chips/saa1064 | 81 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 81 insertions(+) create mode 100644 doc/chips/saa1064 diff --git a/doc/chips/saa1064 b/doc/chips/saa1064 new file mode 100644 index 00000000..f73f76bd --- /dev/null +++ b/doc/chips/saa1064 @@ -0,0 +1,81 @@ +Kernel driver `saa1064.o' +======================== + +Status: Testing; + +Supported chips: + * Philips SAA1064 + Prefix: `saa1064' + Addresses scanned: I2C 0x38 - 0x3b (inclusive) + Datasheet: Publicly available at the Philips Semiconductor website + http://semiconductors.philips.com/ + http://www.philipslogic.com/products/i2c/pdf/saa1064.pdf + + +Author: Sascha Volkenandt + +Module Parameters +----------------- + +* force: short array (min = 1, max = 48) + List of adapter,address pairs to boldly assume to be present +* force_saa1064: short array (min = 1, max = 48) + List of adapter,address pairs which are unquestionably assumed to + contain a `saa1064' chip +* ignore: short array (min = 1, max = 48) + List of adapter,address pairs not to scan +* ignore_range: short array (min = 1, max = 48) + List of adapter,start-addr,end-addr triples not to scan +* probe: short array (min = 1, max = 48) + List of adapter,address pairs to scan additionally +* probe_range: short array (min = 1, max = 48) + List of adapter,start-addr,end-addr triples to scan additionally + + +Description +----------- +The SAA1064 is a 4-digit LED driver chip for the I2C bus produced by Philips +Semiconductors. It is designed to provide a byte I2C interface to up to 4 +separate 4-digit displays (16 digits). + +This device has eight write-only registers, five are used for a control byte +and the four digit values. + +For more informations see the datasheet. + + +Accessing SAA1064 via /proc interface +------------------------------------- + +On detection (i.e. insmod, modprobe et al.), directories are being +created for each detected SAA1064: + +/proc/sys/dev/sensors/saa1064-<0>-<1>/ +where <0> is the bus the chip was detected on (e. g. i2c-0) +and <1> the chip address ([38..3b]): +./saa1064-i2c-0-38/ + +Inside these directories, there are four files each: +bright, test, disp and refresh + +The bright, test and disp files are read-write. + +Writing bright sets the output current to the LEDs connected to the +chip and thus the brightness. Range is from 0 to 7 (inclusive). Reading +gives you the last known value. + +Writing test sets the segment test mode (all LEDs lit regardless of +the digit values) on/off (values 0/1). Reading gives you the last +known value. + +Writing up to four values to disp sets the digits. Each value represents +one segment, while each bit represents one LED of the segment (seven bars +and one dot usually). Reading gives you the last known value. + +The refresh file is read-only. You can't read anything from it, but +reading it will trigger a refresh in case a power-loss has occurred since +the last refresh. + +On module initialization the chip is configured for segment test (test=1), +full brightness (bright=7), all digit values zeroed. +