@Charles It works! Why, I don't know. stty wants odd parity, picocom no parity. This is beyond me for now.
pi@raspberrypi ~ $ stty --file /dev/ttyAMA0 1200 cs7 ixon -parenb
pi@raspberrypi ~ $ cat /dev/ttyAMA0
5
ADCO 012345678901 L
OPTARIF HC.. <
ISOUSC 30 9
HCHC 002698197 0
HCHP 010687090 2
PTEC HP..
IINST 003 Z
IMAX 038 J
PAPP 00680 /
HHPHC A ,
MOTDETAT 000000 B
or with picocom:
pi@raspberrypi ~ $ picocom --baud 1200 --flow x --parity n --databits 7 /dev/ttyAMA0
picocom v1.7
port is : /dev/ttyAMA0
flowcontrol : xon/xoff
baudrate is : 1200
parity is : none
databits are : 7
escape is : C-a
local echo is : no
noinit is : no
noreset is : no
nolock is : no
send_cmd is : sz -vv
receive_cmd is : rz -vv
imap is :
omap is :
emap is : crcrlf,delbs,
Terminal ready
&4Nc
HCHC 002698197 0
HCHP 010687195 8
PTEC HP..
IINST 012 Z
IMAX 038 J
PAPP 02840 /
HHPHC A ,
MOTDETAT 000000
Thanks for using picocom