NAME¶
streamer - stream file data into HAL in real time
SYNOPSIS¶
loadrt streamer depth=depth1[,depth2...]
cfg=string1[,string2...]
DESCRIPTION¶
streamer and halstreamer(1) are used together to
stream data from a file into the HAL in real time. streamer is a
realtime HAL component that exports HAL pins and creates a FIFO in shared
memory. hal_streamer is a non-realtime program that copies data from
stdin into the FIFO, so that streamer can write it to the HAL
pins.
OPTIONS¶
depth=depth1[,depth2...]
Sets the depth of the FIFO that the realtime
streamer creates to receive data from the non-realtime
hal-streamer. Multiple values of depth (separated by commas) can
be specified if you need more than one FIFO (for example if you want to stream
data to two different realtime threads).
cfg=string1[,string2...]
Defines the set of HAL pins that
streamer exports
and later writes data to. One
string must be supplied for each FIFO,
separated by commas.
streamer exports one pin for each character in
string. Legal characters are:
•F, f (float pin)
•B, b (bit pin)
•S, s (s32 pin)
•U, u (u32 pin)
FUNCTIONS¶
streamer.N
One function is created per FIFO, numbered from
zero.
PINS¶
streamer.N.pin.M output
Data from column M of the data in FIFO N
appears on this pin. The pin type depends on the config string.
streamer.N.curr-depth s32 output
Current number of samples in the FIFO. When this reaches
zero, new data will no longer be written to the pins.
streamer.N.empty bit output
TRUE when the FIFO N is empty, FALSE when valid
data is available.
streamer.N.enable bit input
When TRUE, data from FIFO N is written to the HAL
pins. When false, no data is transferred. Defaults to TRUE.
streamer.N.underruns s32 read/write
The number of times that sampler has tried to
write data to the HAL pins but found no fresh data in the FIFO. It increments
whenever empty is true, and can be reset by the setp
command.
streamer.N.*clock bit input
Clock for data as specified by the clock-mode pin
streamer.N.*clock-mode s32 input
Defines behavior of clock pin:
•0 (default) free run at every
iteration
•1 clock on falling edge of clock pin
•2 clock on rising edge of clock pin
•3 clock on any edge of clock pin
BUGS¶
Should an enable HAL pin be added, to allow streaming to be turned
on and off?
AUTHOR¶
Original version by John Kasunich, as part of the LinuxCNC
project. Improvements by several other members of the LinuxCNC development
team.
REPORTING BUGS¶
Report bugs to jmkasunich AT users DOT sourceforge DOT net
COPYRIGHT¶
Copyright © 2006 John Kasunich. This is free software; see
the source for copying conditions. There is NO warranty; not even for
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
