device_drivers/can/can327.rst

1 .. SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause)
7 --------
14 -----------
26 -------------
33 order to fake full-duplex operation.
36 enough to implement simple request-response protocols (such as OBD II),
50 -----------
59 ----------------------------------
68            --debug \
69            --speed 38400 \
70            --eightbits \
71            --noparity \
72            --onestopbit \
73            --iflag -ICRNL,INLCR,-IXOFF \
88 500000 bit/s is a common rate for OBD-II diagnostics.
97 ------------------------------------
118 ----------------------
127 - Command mode
128 - Reception mode
130 In command mode, it expects one command per line, terminated by CR.
167 mode (using "``AT PB``", see code or datasheet).
170 Once a frame has been sent and wait-for-reply mode is on (``ATR1``,
171 configured on ``listen-only=off``), or when the reply timeout expires
172 and the driver sets the controller into monitoring mode (``ATMA``),
183 The ELM327 will receive both SFF and EFF frames - the current CAN
188 the monitoring mode, print "BUFFER FULL" and drop back into command
189 mode. Note that in this case, unlike with other error messages, the
198 ------------------------------------
200 - Clone devices ("v1.5" and others)
211   "receive reply" mode, in which it *does* ACK any received frames.
214   reception mode on its own and can327 will fall back to "``AT MA``"
221 - All versions
224   between input/output mode as quickly as possible.
230   We don't have a way to get real-time notifications on CAN errors.
232   we don't poll it as it would force us to interrupt reception mode.
235 - Versions prior to 1.4b
237   These versions do not send CAN ACKs when in monitoring mode (AT MA).
243   command, and the "listen-only" CAN option will take effect.
246 - Versions prior to 1.4
249   change bitrate or SFF/EFF mode on-the-fly. This will have to be
254 - Versions prior to 1.3
270 --------------------------------
272 - No 8/7 timing.
278   This mode is not currently implemented.
280 - No evaluation of command responses.
288 - No use of hardware CAN ID filtering
292   filters available through "``AT CF xxx``" and "``AT CM xxx``" would be
299 ------------------------------------------
324 ------------------------------
327 the bus. This is correct when it is plugged into a OBD-II socket, but