Max # of channels JR Module will handle in PPM
#2
The maximum number of channels that you can have in PPM mode, per the official specification is 8 channels.

However, you can have more PPM channels if you increased the frame rate.  This is what Graupner and Multiplex do with their radio systems.  The PPM specification calls for 2.2ms x Number of channels +  at least 4.9ms.  With a typical 8 channel radio that gives you a frame time of 22.5ms, which is a frame rate of 44.4 times per second.  32 channels would require more than 75ms, which is ~13 frames per second, making it too slow really for controlling a RC model - especially if dropped frames occur.  XPS transmitter modules support up to 32 channels in PPM mode.

Long frame times means a lot of latency, which iis why protocols like Xtreme, XBUS, SBUS, XJT, etc. exist.  The Xtreme protocol supports up to 256 channels, and a frame rate as low as 3ms with 4 channels.
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RE: Max # of channels JR Module will handle in PPM - by XPS - 04-29-2022, 11:14 AM



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