Yocto-led
Normally, the Yocto-led is used to indicate that the module is working smoothly. The Yocto-led then
emits a low blue light which varies slowly, mimicking breathing. The Yocto-led stops breathing when
the module is not communicating any more, as for instance when powered by a USB hub which is
disconnected from any active computer.
When you press the Yocto-button, the Yocto-led switches to Yocto-beacon mode. It starts flashing
faster with a stronger light, in order to facilitate the localization of a module when you have several
identical ones. It is indeed possible to trigger off the Yocto-beacon by software, as it is possible to
detect by software that a Yocto-beacon is on.
The Yocto-led has a third functionality, which is less pleasant: when the internal software which
controls the module encounters a fatal error, the Yocto-led starts emitting an SOS in morse
1
. If this
happens, unplug and re-plug the module. If it happens again, check that the module contains the
latest version of the firmware, and, if it is the case, contact Yoctopuce support
2
.
Current sensor
Each Yocto-module is able to measure its own current consumption on the USB bus. Current supply
on a USB bus being quite critical, this functionality can be of great help. You can only view the
current consumption of a module by software.
Serial number
Each Yocto-module has a unique serial number assigned to it at the factory. For Yocto-GPS
modules, this number starts with YGNSSMK1. The module can be software driven using this serial
number. The serial number cannot be modified.
Logical name
The logical name is similar to the serial number: it is a supposedly unique character string which
allows you to reference your module by software. However, in the opposite of the serial number, the
logical name can be modified at will. The benefit is to enable you to build several copies of the same
project without needing to modify the driving software. You only need to program the same logical
name in each copy. Warning: the behavior of a project becomes unpredictable when it contains
several modules with the same logical name and when the driving software tries to access one of
these modules through its logical name. When leaving the factory, modules do not have an assigned
logical name. It is yours to define.
2.2. Specific elements
The receiver
The Yocto-GPS is based on a GNSS SL869 receiver produced by
Telit
. It has 32 channels and can
compute up to 10 positions per second.
Satellite reception led
The green led (Fix Sat.) on the module indicates the state of the satellite reception. It stays on when
the reception is satisfactory. It blinks fast when the module searches for satellites. With an
appropriate reception, the Yocto-GPS can obtain a position in less than 35 seconds after a cold start.
Moreover, the Yocto-GPS has a small battery enabling the GPS to remember during several hours
the position of the last seen satellites, enabling a hot start in a few seconds only in most cases. In
case of a particularly degraded satellite reception, obtaining a first position can take up to 5 minutes.
The antenna connector
The Yocto-GPS needs an antenna to work. To maximize reception quality, the Yocto-GPS is
designed to work with an active external antenna (powered seamlessly in 3.3V), connected with a
1
short-short-short long-long-long short-short-short
2
support@yoctopuce.com
2. Presentation
6
www.yoctopuce.com
Summary of Contents for Yocto-GPS
Page 1: ...Yocto GPS User s guide...
Page 2: ......
Page 6: ...22 Characteristics 557 Blueprint 559 Index 561...
Page 10: ...4 www yoctopuce com...
Page 14: ...8 www yoctopuce com...
Page 18: ...12 www yoctopuce com...
Page 22: ...16 www yoctopuce com...
Page 38: ...32 www yoctopuce com...
Page 42: ...36 www yoctopuce com...
Page 54: ...48 www yoctopuce com...
Page 72: ...66 www yoctopuce com...
Page 92: ...86 www yoctopuce com...
Page 122: ...116 www yoctopuce com...
Page 132: ...126 www yoctopuce com...
Page 564: ...22 Characteristics 558 www yoctopuce com...
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