Here is what the datasheet says about this:
"If judge bit is 1, it means frequency mode. If judge bit is 0,
it means duty cycle mode."
But this is plain wrong. Reality proves this is the other way around.
Depending on the chip, the limit value for the buzzer is between 25 and 35 Ω,
so this code set the limit for continuity to 25 Ω to be on the safe side.
Disable drivers that need serial port support if libserialport is not found.
Also, disable building various other serial port related code in that case.
Most Metex DMMs use e.g. " mV" as unit field, others use "mV ",
though. Support these (and other) whitespace variants by stripping all
spaces and only comparing non-space characters.
This DMM is not using the standard bits in the FS9922 protocol/structure
to indicate the "volt" and "diode mode" flags. Instead, it only sets the
user-defined bit "z1" to indicate both "diode mode" and "volt".
This fixes#142.
Use the same functions and structs as the other DMM protocol parsers
in hardware/common/dmm. Among other things, this allows the functions
to be used from drivers in a generic way, e.g. in serial-dmm, uni-t-dmm,
and possibly other drivers.
Some unusual modes required re-parsing the value. Instead of assigning the
re-parsed value to *floatval, it was reassigned directly to *analog->data;
however, analog->data is not initialized at this point, causing a segfault.
This situation was created when moving the radioshack-dmm code to serial-dmm,
with the segfault not being observed at that time.
Do not write directly to analog->data, but instead use the intermediate
variable rawval.
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Convert bit masks from hardcoded hex values to bit shifts. For example 0x80
becomes (1 << 7). This also fixes a typo error in the definition of INFO_DIODE.
Add comments explaining that some case values in sr_rs9lcd_parse() are meant to
fall through without a 'break;', and explain some of the unusual modes.
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Use the infrastructure of serial-dmm to handle the RadioShack 22-812,
and completely remove radioshack-dmm.
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Move the parsing part of radioshack-dmm into a separate protocol
parser, following the model from hardware/common/dmm.
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
strcmp(buf + 9, " mA") does not work because buf is CR-terminated,
while " mA" is NUL-terminated.
Drop ambiguities arising from the termination of the strings, and
only compare the characters we care about, using strncmp().
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
When the parser found a space, it treated it as an invalid digit
and discarded the whole packet. This behavior was incorrect on
2000 count devices, where the first digit can be sent as a space
rather than a '0'.
Convert spaces to '0' and parse them as usual.
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Merge parts of the tekpower-dmm code (the chip of the TekPower
TP4000ZC seems to be an FS9721_LP3 too) and rework parts of the functions.
Adapt the tekpower-dmm and uni-t-dmm code accordingly.
The Fortune Semiconductor FS9721_LP3 and FS9721B/Q100 DMM chips are very
similar and the protocol looks identical.
Tested on a Voltcraft VC-820 (FS9721_LP3) with the uni-t-dmm driver
(needs some small changes, tbd).