User manual

Technical reference 30
Copyright 2004 Pico Technology Limited. All rights reserved.
Arguments:
channel
-
Specifies from which channel to read temperature.
Should be 0 for
CJC, 1 for Channel 1, 2 for Channel 2 and so on.
temp
- Pointer to a location where readings are to be placed. Each reading
should be compared with 2147483647L or LONG_MAX (include
limits.h) to check for overflows.
An overflow occurs when the input
signal is higher than the measuring range of the USB TC-08.
filtered
- Specifies whether or not to filter the data.
The readings are median
filtered if set to 1. 0 causes the unfiltered temperature to be stored in
temp
. The filter has a depth defined by the filter factor, set during a
usb_legacy_set_channel
call.
Returns:
0
- Use
usb_tc08_get_last_error
.
1
- Temperature retrieval successful.
Note: This function should not be called unless you are operating the USB TC-08 in legacy mode,
having called
usb_tc08_legacy_run
.
3.3.4.4 usb_tc08_legacy_get_cold_junction
short usb_tc08_legacy_get_cold_junction (
long * temp,
short
handle)
This routine retrieves a cold junction temperature reading. This can also be achieved by passing
channel = 0 to
usb_tc08_get_temp
. Temperatures are returned in hundredths of a degree Centigrade.
Normally, you do not need to worry about the cold junction temperature, as the driver automatically
uses it to compensate thermocouples. It can, however, be useful as an indication of ambient
temperature.
Arguments:
handle
- Specifies USB TC-08 unit.
temp
- Pointer to a location where the temperature reading is to be stored.
Returns:
0
- Use
usb_tc08_get_last_error
.
1
- Retrieval of cold junction temperature reading successful.
3.3.4.5 usb_tc08_legacy_get_driver_version
short usb_tc08_legacy_get_driver_version (void)
This routine returns the driver version. This is useful when you need to find out if the latest driver is being