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1=========================2Kernel driver i2c-parport3=========================4 5Author: Jean Delvare <jdelvare@suse.de>6 7This is a unified driver for several i2c-over-parallel-port adapters,8such as the ones made by Philips, Velleman or ELV. This driver is9meant as a replacement for the older, individual drivers:10 11 * i2c-philips-par12 * i2c-elv13 * i2c-velleman14 * video/i2c-parport15 (NOT the same as this one, dedicated to home brew teletext adapters)16 17It currently supports the following devices:18 19 * (type=0) Philips adapter20 * (type=1) home brew teletext adapter21 * (type=2) Velleman K8000 adapter22 * (type=3) ELV adapter23 * (type=4) Analog Devices ADM1032 evaluation board24 * (type=5) Analog Devices evaluation boards: ADM1025, ADM1030, ADM103125 * (type=6) Barco LPT->DVI (K5800236) adapter26 * (type=7) One For All JP1 parallel port adapter27 * (type=8) VCT-jig28 29These devices use different pinout configurations, so you have to tell30the driver what you have, using the type module parameter. There is no31way to autodetect the devices. Support for different pinout configurations32can be easily added when needed.33 34Earlier kernels defaulted to type=0 (Philips). But now, if the type35parameter is missing, the driver will simply fail to initialize.36 37SMBus alert support is available on adapters which have this line properly38connected to the parallel port's interrupt pin.39 40 41Building your own adapter42-------------------------43 44If you want to build you own i2c-over-parallel-port adapter, here is45a sample electronics schema (credits go to Sylvain Munaut)::46 47 Device PC48 Side ___________________Vdd (+) Side49 | | |50 --- --- ---51 | | | | | |52 |R| |R| |R|53 | | | | | |54 --- --- ---55 | | |56 | | /| |57 SCL ----------x--------o |-----------x------------------- pin 258 | \| | |59 | | |60 | |\ | |61 SDA ----------x----x---| o---x--------------------------- pin 1362 | |/ |63 | |64 | /| |65 ---------o |----------------x-------------- pin 366 \| | |67 | |68 --- ---69 | | | |70 |R| |R|71 | | | |72 --- ---73 | |74 ### ###75 GND GND76 77Remarks:78 - This is the exact pinout and electronics used on the Analog Devices79 evaluation boards.80 - All inverters::81 82 /|83 -o |-84 \|85 86 must be 74HC05, they must be open collector output.87 - All resitors are 10k.88 - Pins 18-25 of the parallel port connected to GND.89 - Pins 4-9 (D2-D7) could be used as VDD is the driver drives them high.90 The ADM1032 evaluation board uses D4-D7. Beware that the amount of91 current you can draw from the parallel port is limited. Also note that92 all connected lines MUST BE driven at the same state, else you'll short93 circuit the output buffers! So plugging the I2C adapter after loading94 the i2c-parport module might be a good safety since data line state95 prior to init may be unknown.96 - This is 5V!97 - Obviously you cannot read SCL (so it's not really standard-compliant).98 Pretty easy to add, just copy the SDA part and use another input pin.99 That would give (ELV compatible pinout)::100 101 102 Device PC103 Side ______________________________Vdd (+) Side104 | | | |105 --- --- --- ---106 | | | | | | | |107 |R| |R| |R| |R|108 | | | | | | | |109 --- --- --- ---110 | | | |111 | | |\ | |112 SCL ----------x--------x--| o---x------------------------ pin 15113 | | |/ |114 | | |115 | | /| |116 | ---o |-------------x-------------- pin 2117 | \| | |118 | | |119 | | |120 | |\ | |121 SDA ---------------x---x--| o--------x------------------- pin 10122 | |/ |123 | |124 | /| |125 ---o |------------------x--------- pin 3126 \| | |127 | |128 --- ---129 | | | |130 |R| |R|131 | | | |132 --- ---133 | |134 ### ###135 GND GND136 137 138If possible, you should use the same pinout configuration as existing139adapters do, so you won't even have to change the code.140 141 142Similar (but different) drivers143-------------------------------144 145This driver is NOT the same as the i2c-pport driver found in the i2c146package. The i2c-pport driver makes use of modern parallel port features so147that you don't need additional electronics. It has other restrictions148however, and was not ported to Linux 2.6 (yet).149 150This driver is also NOT the same as the i2c-pcf-epp driver found in the151lm_sensors package. The i2c-pcf-epp driver doesn't use the parallel port as152an I2C bus directly. Instead, it uses it to control an external I2C bus153master. That driver was not ported to Linux 2.6 (yet) either.154 155 156Legacy documentation for Velleman adapter157-----------------------------------------158 159Useful links:160 161- Velleman http://www.velleman.be/162- Velleman K8000 Howto http://howto.htlw16.ac.at/k8000-howto.html163 164The project has lead to new libs for the Velleman K8000 and K8005:165 166 LIBK8000 v1.99.1 and LIBK8005 v0.21167 168With these libs, you can control the K8000 interface card and the K8005169stepper motor card with the simple commands which are in the original170Velleman software, like SetIOchannel, ReadADchannel, SendStepCCWFull and171many more, using /dev/velleman.172 173 - http://home.wanadoo.nl/hihihi/libk8000.htm174 - http://home.wanadoo.nl/hihihi/libk8005.htm175 - http://struyve.mine.nu:8080/index.php?block=k8000176 - http://sourceforge.net/projects/libk8005/177 178 179One For All JP1 parallel port adapter180-------------------------------------181 182The JP1 project revolves around a set of remote controls which expose183the I2C bus their internal configuration EEPROM lives on via a 6 pin184jumper in the battery compartment. More details can be found at:185 186http://www.hifi-remote.com/jp1/187 188Details of the simple parallel port hardware can be found at:189 190http://www.hifi-remote.com/jp1/hardware.shtml191