Thread: Venus Series City Navigator China NT CHS 2011.11

compare this to the official version, the map size is different almost by half.
official map - 1.29GB
venus map - 753MB

why so much difference?

Originally Posted by ander7724

compare this to the official version, the map size is different almost by half.
official map - 1.29GB
venus map - 753MB

why so much difference?

Two subfiles QSIINDEX.QSI (for Quick Spelling Input) and ISM.IDX (maybe for Intersection lookup) are removed from the official map, hence the smaller size. These two subfiles only work on official retail products sold in China. So it makes no sense to keep them in the Venus map which will be installed on non-Garmin-China devices by most people.

If you really need these two subfiles, you can use gmaptool to extract them from the official map then join them to the Venus map.

Originally Posted by ander7724

Thanks for the explanation, so is there's any benefit/advantage if i'm using a garmin GPS unit if those 2 files was included?
Anyway did the '006B082300.bin' confirm corrected the offset for the official NT CHINA 2011.11 map?

As said before, only the firmware in Garmin China products can recognize these two subfiles. So even if your device is an official, say Garmin US, product you won't be able to take advantage of the features provided by these two subfiles, unless you can find a way to flash your device to Chinese firmware.

It is a myth or misunderstanding that the file '006B082300.bin' can correct the shift/offset in an official Garmin China map. In reality, the map itself is never modified, let alone corrected. The coordinates of the map are not corrected neither when they are displayed on screen or recorded in SD card.

What contained in the bin file is actually a piece of code to add shift/offset to the coordinates received from the GPS chipset before they are sent to the navigation software. The same algorithm used to shift the China map is used to shift the GPS coordinates. When the navigation software displays the shifted GPS location on the shifted map, it looks as if there was no shift to the user because the amount of shift is the same. An illusion after all. However, the recorded waypoints, routes and tracks will all have shifted coordinates which cannot be exchanged with Google Earth and other regular GPS products/software.

Similar to the two subfiles above, only the firmware/software in some Garmin China and Garmin Taiwan products can recognize this bin file and activate the shift adding (not the mythical correcting) feature. That's why most non-Garmin-China/Taiwan devices have to use shift corrected maps like Venus maps.

Originally Posted by betahash

ander7724:

the most remarkable advantage from Venus is the resultant performance. With official release the QSI (Quick Search Index) and ISM (precious & better cross-boarder/blocks plan) are expected, but GS QSI is only available in limited portion of Garmin Series hardware.

I think, without confirm with syzygy, ISM is no way to work with Venus, nor could it be Venus-ed.

mentioned bin file from hardware firmware, must exist with official map, and must be removed with Venus map.

Originally Posted by syzygy

As said before, only the firmware in Garmin China products can recognize these two subfiles. So even if your device is an official, say Garmin US, product you won't be able to take advantage of the features provided by these two subfiles, unless you can find a way to flash your device to Chinese firmware.

It is a myth or misunderstanding that the file '006B082300.bin' can correct the shift/offset in an official Garmin China map. In reality, the map itself is never modified, let alone corrected. The coordinates of the map are not corrected neither when they are displayed on screen or recorded in SD card.

What contained in the bin file is actually a piece of code to add shift/offset to the coordinates received from the GPS chipset before they are sent to the navigation software. The same algorithm used to shift the China map is used to shift the GPS coordinates. When the navigation software displays the shifted GPS location on the shifted map, it looks as if there was no shift to the user because the amount of shift is the same. An illusion after all. However, the recorded waypoints, routes and tracks will all have shifted coordinates which cannot be exchanged with Google Earth and other regular GPS products/software.

Similar to the two subfiles above, only the firmware/software in some Garmin China and Garmin Taiwan products can recognize this bin file and activate the shift adding (not the mythical correcting) feature. That's why most non-Garmin-China/Taiwan devices have to use shift corrected maps like Venus maps.

Thanks you guys for the explanations... Now i understand.

Originally Posted by syzygy

Similar to the two subfiles above, only the firmware/software in some Garmin China and Garmin Taiwan products can recognize this bin file and activate the shift adding (not the mythical correcting) feature.

This sounds strange to me, cause this bin file was provided by Garmin USA to customers who bought the China NT map from their website and faced the shifting issue. After this, USA/EU devices had also no shifting anymore. Please note that the file is original from Garmin. Maybe its not limited to China or Taiwan devices, maybe the bin file works only for a limited amount of Nuvi models

Originally Posted by tom1807

This sounds strange to me, cause this bin file was provided by Garmin USA to customers who bought the China NT map from their website and faced the shifting issue. After this, USA/EU devices had also no shifting anymore. Please note that the file is original from Garmin. Maybe its not limited to China or Taiwan devices, maybe the bin file works only for a limited amount of Nuvi models

You could be right. My info was gathered some time ago and has not been updated. Maybe each .bin file is like a plugin that every Garmin device can recognize, read in, validate then execute if applicable. If not every device, at least on new models and old models with firmware upgrade. But I simply have no access to every Garmin device to verify this. I would encourage readers of this forum to try the official shifted China map on their Garmin devices with and without the bin file then compare the results.

Originally Posted by syzygy

However, the recorded waypoints, routes and tracks will all have shifted coordinates which cannot be exchanged with Google Earth and other regular GPS products/software.

Some good news and updates regarding the saved data. The new Oregon 450 and Oregon 550 sold by Garmin China can save both un-shifted and shifted coordinates now. A great improvement. Other new devices like 62S sold in China may have the same feature, but not confirmed yet.

For Oregon 450:
If no SD card is inserted, the coordinates saved in the internal memory will be shifted.
If an SD card is inserted, the coordinates will be saved in SD card only but are un-shifted.

For Oregon 550:
If an SD card is inserted, shifted and un-shifted coordinates will be saved in the internal memory and SD card respectively at the same time.
Not sure which verison will be saved when no SD is inserted. Most likely shifted.