Gps mode driver

DJ7WL , Sep 9, LB5HG , Oct 22, Hi Guys. Manny here N2ITR. I just finished interfacing my MD to Windows 7. I can "talk" to it and read from it. I was initially successful with programming an analog channel just to verify data transfer.

It works. Here are some of the issues I ran into: 1 The supplied CPS computer programming software reported the radio as the "wrong model" when I initially tried to write to it or read in from it. Solution: Find an updated software higher than rev 1. I am now using v 1. It works perfectly. It is a straight-through cable.

It requires a separate driver that no version of Windows I'll call it the Windows Driver Cloud supplies. Caveat: Using higher line speeds does not necessarily increase the precision of the timing device.

Higher line speeds are not necessarily helpful for the NMEA driver, either. They can be used to accomodate for an amount of data that does not fit into a 1-second cycle at bps, but high-speed high-volume NMEA data is likely to cause trouble with the serial line driver since NMEA supports no protocol handshake.

Any device that is exclusively used for time synchronisation purposes should be configured to transmit the relevant data only, e. The last GPS sentence that is accepted or rejected is written to the clockstats file and available with ntpq -c clockvar. Filtered sentences are not logged. If the 0x mode bit is on and clockstats is enabled, several extra counters will be appended to the NMEA sentence that gets logged.

For example: Configuring NMEA Refclocks might give further useful hints for specific hardware devices that exhibit strange or curious behaviour. Drivers that support distance based tracking fix sessions and time based tracking fix sessions must support simultaneously a single shot fix session, a distance based tracking fix session and a time based tracking fix session. Whether the driver supports multiple simultaneous fix sessions or not is expressed by a well-defined driver capability parameter.

If a driver does not explicitly support multiple parallel fix sessions, it must fail a new fix-session request if a session of the same fix type is already started and active. If multiple fix session support is not present, the onus is on the HLOS component to ensure that multiple GNSS requests coming from the high-level applications are multiplexed and mapped into a single fix session request to the GNSS driver.

The GNSS driver is not required to support multiple parallel fix sessions of the same type. In future releases it will be considered to enable the GNSS adapter to directly start sessions with the GNSS driver for every fix request obtained from the upper layers of the location platform, rather than doing the session multiplexing itself. Support of multiplexing of fix sessions in the GNSS adapter simplifies the driver implementation as it does not require it to handle multiple sessions of the same type for an application or implementation of multiplexing, it reduces the memory usage in the driver, and it does not require the GNSS adapter to handle the case of the HLOS starting a number of fix sessions larger than what is supported by the GNSS driver.

Different tiers of devices and different drivers would support a different number of concurrent fix sessions, thus this case would need to be handled, introducing complexity in the GNSS adapter to handle all cases. Therefore, in Windows 10 the GNSS adapter will only implement the single fix session of each supported type and will ignore the multiple fix session support by the driver until we have a need for this functionality.

This is required at least until the GNSS adapter handles multiplexing of fix sessions of the same type and it may even be require later on to handle the case of more simultaneous fix sessions active than the number supported by the GNSS driver. Fix sessions are uniquely identified by a fix session ID. No positional information can be retrieved by the HLOS outside the context of a fix session.

The GNSS driver must allow modification of the session parameters on the fly to facilitate the multiplexing operation by the HLOS component, without the need of restarting the fix session. Additionally the driver should natively support advanced fix types such as tracking. As stated earlier, supporting additional fix types implies that even if the driver does not support multiple fix sessions of the same type, it must support simultaneously at least one fix session of a supported fix type.

The HLOS component does not multiplex different fix types into a single type. Device power policy: The GNSS driver should manage the power policy of its device and should handle the power management events raised by the OS. The GNSS driver should be configurable to optionally disable power management. The exact power management that needs to be done in a GNSS device in the different system power states needs to be adapted according to the capabilities of the GNSS device does it support offloaded operations or not , whether there are actual offloaded operations active, and how the communication between the system and GNSS device gets done.

In general the expectations are as follows:. The GNSS device will work in the lowest power mode possible when there are no active sessions or offloaded operations, regardless of the system power state.

In case of offloaded scenarios, again regardless of the system power state, the GNSS device may need to check for position at different intervals or receive notifications and thus the GNSS device may need to stay in D0 state even during connected standby this is the screen-off sleep state , but still the hardware needs to reduce the power consumption to the minimum.

In general GNSS devices connected via USB must be able to enter a low-power D2 suspend state after they have no fix sessions or offloaded operations ongoing and the USB bus interface enters the suspend state. All sleep and wake power transitions must be signaled over the USB bus. If the GNSS device has fix sessions active or offloaded operations, the device must be able to use in-band, USB resume signaling to wake the SoC or core silicon from connected standby. Devices that do not support connected standby will have all offloaded operations cancelled at the time when the device goes to modern standby or hibernation.