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Diffstat (limited to 'Documentation/input/walkera0701.txt')
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diff --git a/Documentation/input/walkera0701.txt b/Documentation/input/walkera0701.txt deleted file mode 100644 index 49e3ac60dcef..000000000000 --- a/Documentation/input/walkera0701.txt +++ /dev/null @@ -1,109 +0,0 @@ - -Walkera WK-0701 transmitter is supplied with a ready to fly Walkera -helicopters such as HM36, HM37, HM60. The walkera0701 module enables to use -this transmitter as joystick - -Devel homepage and download: -http://zub.fei.tuke.sk/walkera-wk0701/ - -or use cogito: -cg-clone http://zub.fei.tuke.sk/GIT/walkera0701-joystick - - -Connecting to PC: - -At back side of transmitter S-video connector can be found. Modulation -pulses from processor to HF part can be found at pin 2 of this connector, -pin 3 is GND. Between pin 3 and CPU 5k6 resistor can be found. To get -modulation pulses to PC, signal pulses must be amplified. - -Cable: (walkera TX to parport) - -Walkera WK-0701 TX S-VIDEO connector: - (back side of TX) - __ __ S-video: canon25 - / |_| \ pin 2 (signal) NPN parport - / O 4 3 O \ pin 3 (GND) LED ________________ 10 ACK - ( O 2 1 O ) | C - \ ___ / 2 ________________________|\|_____|/ - | [___] | |/| B |\ - ------- 3 __________________________________|________________ 25 GND - E - - -I use green LED and BC109 NPN transistor. - -Software: - -Build kernel with walkera0701 module. Module walkera0701 need exclusive -access to parport, modules like lp must be unloaded before loading -walkera0701 module, check dmesg for error messages. Connect TX to PC by -cable and run jstest /dev/input/js0 to see values from TX. If no value can -be changed by TX "joystick", check output from /proc/interrupts. Value for -(usually irq7) parport must increase if TX is on. - - - -Technical details: - -Driver use interrupt from parport ACK input bit to measure pulse length -using hrtimers. - -Frame format: -Based on walkera WK-0701 PCM Format description by Shaul Eizikovich. -(downloaded from http://www.smartpropoplus.com/Docs/Walkera_Wk-0701_PCM.pdf) - -Signal pulses: - (ANALOG) - SYNC BIN OCT - +---------+ +------+ - | | | | ---+ +------+ +--- - -Frame: - SYNC , BIN1, OCT1, BIN2, OCT2 ... BIN24, OCT24, BIN25, next frame SYNC .. - -pulse length: - Binary values: Analog octal values: - - 288 uS Binary 0 318 uS 000 - 438 uS Binary 1 398 uS 001 - 478 uS 010 - 558 uS 011 - 638 uS 100 - 1306 uS SYNC 718 uS 101 - 798 uS 110 - 878 uS 111 - -24 bin+oct values + 1 bin value = 24*4+1 bits = 97 bits - -(Warning, pulses on ACK are inverted by transistor, irq is raised up on sync -to bin change or octal value to bin change). - -Binary data representations: - -One binary and octal value can be grouped to nibble. 24 nibbles + one binary -values can be sampled between sync pulses. - -Values for first four channels (analog joystick values) can be found in -first 10 nibbles. Analog value is represented by one sign bit and 9 bit -absolute binary value. (10 bits per channel). Next nibble is checksum for -first ten nibbles. - -Next nibbles 12 .. 21 represents four channels (not all channels can be -directly controlled from TX). Binary representations are the same as in first -four channels. In nibbles 22 and 23 is a special magic number. Nibble 24 is -checksum for nibbles 12..23. - -After last octal value for nibble 24 and next sync pulse one additional -binary value can be sampled. This bit and magic number is not used in -software driver. Some details about this magic numbers can be found in -Walkera_Wk-0701_PCM.pdf. - -Checksum calculation: - -Summary of octal values in nibbles must be same as octal value in checksum -nibble (only first 3 bits are used). Binary value for checksum nibble is -calculated by sum of binary values in checked nibbles + sum of octal values -in checked nibbles divided by 8. Only bit 0 of this sum is used. - |