I have a PPP connection between my BeagleBone Black running Angstrom and my MacBook Pro, over a pair of 3DR radios (actually the Hobbyking version).
The radios work fine -- I can connect screen to each end and type to each other.
PPP works -- the log files don't have any errors.
ICMP works -- I can ping with no lost packets, latency of about 200ms, in both direction.
I can connect via SSH from one system to another, but it doesn't quite work as expected: It seems to 'lag' by one character. That is, if I type 'ls<newline>' I will not see the output of ls until I type another character.
I don't think this is a problem at one end -- I can see radio link activity at both ends as soon as I type the character.
SSH via ethernet works as expected.
Another data point: the Send-Q never empties, i.e. netstat always reports something like:
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 128 192.168.1.20:ssh 192.168.1.21:54447 ESTABLISHED
I welcome any ideas.
Thanks,
Tom
Radio config: (I've also tried with ECC and opportunistic resend on)
ATI5
S0: FORMAT=25
S1: SERIAL_SPEED=57
S2: AIR_SPEED=64
S3: NETID=25
S4: TXPOWER=20
S5: ECC=0
S6: MAVLINK=0
S7: OPPRESEND=0
S8: MIN_FREQ=915000
S9: MAX_FREQ=928000
S10: NUM_CHANNELS=50
S11: DUTY_CYCLE=100
S12: LBT_RSSI=0
S13: MANCHESTER=0
S14: RTSCTS=0
/etc/ppp/options on the BBB:
ttyO1
57600
mru 296
defaultroute
noaccomp
nopcomp
lock
maxfail 0
lcp-echo-interval 60
local
ipcp-restart 20
/etc/ppp/options on OS X:
192.168.1.21:192.168.1.20
tty.usbserial-AM0263ME
57600
mru 296
debug
logfile /Users/tomd/tmp/ppp.log
noaccomp
nopcomp
nocrtscts
lock
maxfail 0
lcp-echo-interval 60
local
lcp-max-configure 10000
Replies
It seems my problem is just that I'm not using flow control -- when I set the line speed significantly lower than the air speed it works (although slowly). I'll need to get CTS/RTS configured.