1 ========================= 2 Kernel driver i2c-parport 3 ========================= 4 5 Author: Jean Delvare <jdelvare@suse.de> 6 7 This is a unified driver for several i2c-over-parallel-port adapters, 8 such as the ones made by Philips, Velleman or ELV. This driver is 9 meant as a replacement for the older, individual drivers: 10 11 * i2c-philips-par 12 * i2c-elv 13 * i2c-velleman 14 * video/i2c-parport 15 (NOT the same as this one, dedicated to home brew teletext adapters) 16 17 It currently supports the following devices: 18 19 * (type=0) Philips adapter 20 * (type=1) home brew teletext adapter 21 * (type=2) Velleman K8000 adapter 22 * (type=3) ELV adapter 23 * (type=4) Analog Devices ADM1032 evaluation board 24 * (type=5) Analog Devices evaluation boards: ADM1025, ADM1030, ADM1031 25 * (type=6) Barco LPT->DVI (K5800236) adapter 26 * (type=7) One For All JP1 parallel port adapter 27 * (type=8) VCT-jig 28 29 These devices use different pinout configurations, so you have to tell 30 the driver what you have, using the type module parameter. There is no 31 way to autodetect the devices. Support for different pinout configurations 32 can be easily added when needed. 33 34 Earlier kernels defaulted to type=0 (Philips). But now, if the type 35 parameter is missing, the driver will simply fail to initialize. 36 37 SMBus alert support is available on adapters which have this line properly 38 connected to the parallel port's interrupt pin. 39 40 41 Building your own adapter 42 ------------------------- 43 44 If you want to build you own i2c-over-parallel-port adapter, here is 45 a sample electronics schema (credits go to Sylvain Munaut):: 46 47 Device PC 48 Side ___________________Vdd (+) Side 49 | | | 50 --- --- --- 51 | | | | | | 52 |R| |R| |R| 53 | | | | | | 54 --- --- --- 55 | | | 56 | | /| | 57 SCL ----------x--------o |-----------x------------------- pin 2 58 | \| | | 59 | | | 60 | |\ | | 61 SDA ----------x----x---| o---x--------------------------- pin 13 62 | |/ | 63 | | 64 | /| | 65 ---------o |----------------x-------------- pin 3 66 \| | | 67 | | 68 --- --- 69 | | | | 70 |R| |R| 71 | | | | 72 --- --- 73 | | 74 ### ### 75 GND GND 76 77 Remarks: 78 - This is the exact pinout and electronics used on the Analog Devices 79 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 of 91 current you can draw from the parallel port is limited. Also note that 92 all connected lines MUST BE driven at the same state, else you'll short 93 circuit the output buffers! So plugging the I2C adapter after loading 94 the i2c-parport module might be a good safety since data line state 95 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 PC 103 Side ______________________________Vdd (+) Side 104 | | | | 105 --- --- --- --- 106 | | | | | | | | 107 |R| |R| |R| |R| 108 | | | | | | | | 109 --- --- --- --- 110 | | | | 111 | | |\ | | 112 SCL ----------x--------x--| o---x------------------------ pin 15 113 | | |/ | 114 | | | 115 | | /| | 116 | ---o |-------------x-------------- pin 2 117 | \| | | 118 | | | 119 | | | 120 | |\ | | 121 SDA ---------------x---x--| o--------x------------------- pin 10 122 | |/ | 123 | | 124 | /| | 125 ---o |------------------x--------- pin 3 126 \| | | 127 | | 128 --- --- 129 | | | | 130 |R| |R| 131 | | | | 132 --- --- 133 | | 134 ### ### 135 GND GND 136 137 138 If possible, you should use the same pinout configuration as existing 139 adapters do, so you won't even have to change the code. 140 141 142 Similar (but different) drivers 143 ------------------------------- 144 145 This driver is NOT the same as the i2c-pport driver found in the i2c 146 package. The i2c-pport driver makes use of modern parallel port features so 147 that you don't need additional electronics. It has other restrictions 148 however, and was not ported to Linux 2.6 (yet). 149 150 This driver is also NOT the same as the i2c-pcf-epp driver found in the 151 lm_sensors package. The i2c-pcf-epp driver doesn't use the parallel port as 152 an I2C bus directly. Instead, it uses it to control an external I2C bus 153 master. That driver was not ported to Linux 2.6 (yet) either. 154 155 156 Legacy documentation for Velleman adapter 157 ----------------------------------------- 158 159 Useful links: 160 161 - Velleman http://www.velleman.be/ 162 - Velleman K8000 Howto http://howto.htlw16.ac.at/k8000-howto.html 163 164 The project has lead to new libs for the Velleman K8000 and K8005: 165 166 LIBK8000 v1.99.1 and LIBK8005 v0.21 167 168 With these libs, you can control the K8000 interface card and the K8005 169 stepper motor card with the simple commands which are in the original 170 Velleman software, like SetIOchannel, ReadADchannel, SendStepCCWFull and 171 many more, using /dev/velleman. 172 173 - http://home.wanadoo.nl/hihihi/libk8000.htm 174 - http://home.wanadoo.nl/hihihi/libk8005.htm 175 - http://struyve.mine.nu:8080/index.php?block=k8000 176 - http://sourceforge.net/projects/libk8005/ 177 178 179 One For All JP1 parallel port adapter 180 ------------------------------------- 181 182 The JP1 project revolves around a set of remote controls which expose 183 the I2C bus their internal configuration EEPROM lives on via a 6 pin 184 jumper in the battery compartment. More details can be found at: 185 186 http://www.hifi-remote.com/jp1/ 187 188 Details of the simple parallel port hardware can be found at: 189 190 http://www.hifi-remote.com/jp1/hardware.shtml
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