Blackandtan17: What are you downloading? Is it from Garmin, or from gpsfiledepot? Not sure about how it works from Garmin, but I've already downloaded free files to a folder on my computer from GFD. Once I get the card and the Astro unit, I'll then load them on the card and plug it into the unit.
Either way, you will need to buy Micro SD Card because the Astro has no built in memory. You put the map file on the card using the MapSource CD that came with the unit, and then install the card into the Astro.
HERE'S MY QUESTION:
I ordered my Astro Bundle last night ( $465+$10 shipping from
http://www.notjustgps.com ), and bought a 4 GB Micro SD Card off ebay. Can I put multiple files on it, let say 5 different states from
http://www.gpsfiledeopt.com , and then be able to access them as I need them, or can you only have one map file per card? I bought the card on impulse because it was a decent price, but if I can only put one map file on it at a time, then It was a bad move. I would've then been better off buying multiple small memory cards. However, I'm assuming I can put multiple files on it, but it doesn't really say in the Astro Owner's Manual.
FOUND MY ANSWER:
There are limitations to the size of SD/microSD card used and to the number of detailed mapping segments that can be recognized by a device.
If at the most recent unit software version, these limitations are:
* There is no limitation to the size of SD/microSD card used but the device will only recognize 4GB of detailed mapping
* Each expandable memory device will be able to recognize up to 2,025 detailed mapping segments
If 2,025 detailed mapping segments are loaded to an SD/microSD card but does not reach 4GB worth of data, the unit will not show any more detailed mapping than what is provided by the mapping segments.