@@ -1,3 +1,6 @@
+===========================
+Walkera WK-0701 transmitter
+===========================
Walkera WK-0701 transmitter is supplied with a ready to fly Walkera
helicopters such as HM36, HM37, HM60. The walkera0701 module enables to use
@@ -10,7 +13,8 @@ or use cogito:
cg-clone http://zub.fei.tuke.sk/GIT/walkera0701-joystick
-Connecting to PC:
+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,
@@ -19,7 +23,8 @@ modulation pulses to PC, signal pulses must be amplified.
Cable: (walkera TX to parport)
-Walkera WK-0701 TX S-VIDEO connector:
+Walkera WK-0701 TX S-VIDEO connector::
+
(back side of TX)
__ __ S-video: canon25
/ |_| \ pin 2 (signal) NPN parport
@@ -30,10 +35,10 @@ Walkera WK-0701 TX S-VIDEO connector:
------- 3 __________________________________|________________ 25 GND
E
-
I use green LED and BC109 NPN transistor.
-Software:
+Software
+========
Build kernel with walkera0701 module. Module walkera0701 need exclusive
access to parport, modules like lp must be unloaded before loading
@@ -44,7 +49,8 @@ be changed by TX "joystick", check output from /proc/interrupts. Value for
-Technical details:
+Technical details
+=================
Driver use interrupt from parport ACK input bit to measure pulse length
using hrtimers.
@@ -53,17 +59,29 @@ 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:
+Signal pulses
+-------------
+
+::
+
+ (ANALOG)
+ SYNC BIN OCT
+ +---------+ +------+
+ | | | |
+ --+ +------+ +---
+
+Frame
+-----
+
+::
+
SYNC , BIN1, OCT1, BIN2, OCT2 ... BIN24, OCT24, BIN25, next frame SYNC ..
-pulse length:
+pulse length
+------------
+
+::
+
Binary values: Analog octal values:
288 uS Binary 0 318 uS 000
@@ -80,7 +98,8 @@ pulse length:
(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:
+Binary data representations
+---------------------------
One binary and octal value can be grouped to nibble. 24 nibbles + one binary
values can be sampled between sync pulses.
@@ -100,10 +119,10 @@ 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:
+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.
-
This file require minimum adjustments to be a valid ReST file. Do it, in order to be able to parse it with Sphinx. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> --- Documentation/input/walkera0701.txt | 53 +++++++++++++++++++++++++------------ 1 file changed, 36 insertions(+), 17 deletions(-)