Flash
The Prizm uses the Flash chip for storing boot code and OS update code, the OS itself, as well as the Storage Memory. The flash chip is much slower than the Main Memory, but is much larger.
Note: newer hardware revisions include a Macronix flash instead of a Spansion. Documentation on the new chip is yet to be added, but since a datasheet is available, it shouldn't take very long.
Contents
Hardware Specs
- Manufacturer: Spansion
- Model No.: S29GL256N10TFI02
- Size: 256 Megabits / 32 MB
- Speed: 100ns
- Package: TSO56
- Lead free
- Temp. Rating: -40°C to 85°C
- Power: 2.7V to 3.6V
- Protection: Lowest address sector protected (boot code)
Memory Mapping
The Prizm maps the actual flash chip in a few locations. Firstly, there are two direct access locations available to access the entire flash:
- 0xA0000000 to 0xA1FFFFFF - Cached
- 0x80000000 to 0x81FFFFFF - Same, but non-cached
Addins are executed from the ROM, but the address is virtualized to (todo, 0x300000?)
Reading Files Directly
See the Using the File System tutorial and look at using the Bfile_FindFirst function to get the direct address for files.
Formatting and Mounting
Todo.
OS Updating
Todo. Uses Protocol 7 to load flashing payload to RAM, then receives OS.
Special thanks to Simon Loather for his documentation and for anyone else involved.
