- Mon Mar 02, 2015 5:54 pm
#11128
I am working on a simular project.(Using the eclipse IDE in windows)
I must admit , I am not a wifi expert...
The plan was to send serial (uart) data to an esp-01 that is in SOFTAP mode.
The data consists of a few bytes (20), it is send using the UDP protocol.
The "receiver" is also an ESP-01, that is in STATION autoconnecting mode.
Both units AP and ST have fixed IPaddresses.
The "receiver" generates a PPM signal, using some timers controlled by these 20 bytes.
This PPM signal is connected to a multicopter multiwii flightcontrol board .
The "receiver" will also send serial telemetry data coming from the multiwii to the AP, that can than be presented on e.g. a LCD using I2C.
The problem is that the PPM signal is heavily disturbed by the incoming data.
At the ST side it is even worse then on the AP side.
Also I see a random delay between sending these 20 bytes and receiving them.
Using a fixed transmission interval of 20mSec. the received date will have random delays of ~5mSec.
Did you experience simular behaviour.
I must admit , I am not a wifi expert...
The plan was to send serial (uart) data to an esp-01 that is in SOFTAP mode.
The data consists of a few bytes (20), it is send using the UDP protocol.
The "receiver" is also an ESP-01, that is in STATION autoconnecting mode.
Both units AP and ST have fixed IPaddresses.
The "receiver" generates a PPM signal, using some timers controlled by these 20 bytes.
This PPM signal is connected to a multicopter multiwii flightcontrol board .
The "receiver" will also send serial telemetry data coming from the multiwii to the AP, that can than be presented on e.g. a LCD using I2C.
The problem is that the PPM signal is heavily disturbed by the incoming data.
At the ST side it is even worse then on the AP side.
Also I see a random delay between sending these 20 bytes and receiving them.
Using a fixed transmission interval of 20mSec. the received date will have random delays of ~5mSec.
Did you experience simular behaviour.
- Mon Mar 16, 2015 3:10 pm
#12064
HI, PPM signal can be generated same way as servo signal, little problem is 1 servo pulse is 2ms max but 8 chanel ppm can be 16ms long if you generate that ppm every 20ms you have only 4ms to compute everything.
Only solution is rewrite pwm library and use HW timer for PPM. This is best way. But I havent time to write it
Only solution is rewrite pwm library and use HW timer for PPM. This is best way. But I havent time to write it
- Tue May 19, 2015 4:36 pm
#17901
@milikiller: Have you seen this article ?
http://www.naun.org/main/NAUN/circuitssystemssignal/cssp-102.pdf
It presents the usual cascaded PPM output generation method, as well as a new method requiring a high-resolution timer, starting all pulses in a synchronous way, but requiring no channel reordering.
http://www.naun.org/main/NAUN/circuitssystemssignal/cssp-102.pdf
It presents the usual cascaded PPM output generation method, as well as a new method requiring a high-resolution timer, starting all pulses in a synchronous way, but requiring no channel reordering.
