Super Famicom Channel Map (Hardware Channel $0124)
(Goes to $7E9A34) $00-$01 : Unused. $02 : Unknown (Copies to RAM $1411) $03-$04 : 16-bit Big Endian Data Size (Copies to RAM $140F in Little Endian)
Channel Map Header
(Goes to $7E9BEC) [Everything is checked for the Checksum] $00-$01 : "SF" (0x4653) string. $02 : ??? $03 : ??? $04 : ??? $05 : ??? $06 : Number of Data Blocks (Goes to RAM $4B) $07 : 8-bit Checksum.
(Data Block Header) $00-$01 : 16-bit value, Software Channel ?.?.X.X $02 : Number of Data Chunks in this block (Data Chunk begins here) $00 : Unknown $01-$02 : Software Channel X.X.?.? $03-$08 : Unknown $09 : Data Settings $0A-$0B : Hardware Channel (From here, you can have another Data Chunk, or a Data Block header and repeats)
BS-X supported Software Channels
In Software Channel 1.1.?.? ($0101): 18.104.22.168 ($0400) = Message of the Day 22.214.171.124 ($0700) = Update Download 126.96.36.199 ($0500) = Main Download (Required) 188.8.131.52 ($0600) = Item/Schedule Download
Common Download Header
(Goes to $7E9A34) $00 : AND #$F0 and goes to RAM $1414 $01 : Part Number (Goes to RAM $140E) $02 : Goes to RAM $1411, must be #$00. $03-$04 : Size of Data - 5. (Goes to RAM $140F) $05 : Has to be #$01. $06 : Number of Parts (Goes to RAM $1412) $07-$09 : 24-bit Relative Address to Where the Data should be copied. (Following Data goes to Hardcoded Address+$07)
Message of the Day
The Message of the Day, in Shift-JIS format, gets copied to RAM $7EA1B9
Seems like it's used from updating BS-X BIOS functions on SRAM.
(Goes to RAM $7FC000) $00 - Unknown. (Main Copy Header starts here) $01 - Check. Just don't put a negative value. $02 - Unused. $03-$04 : 16-bit Data Size. (Big Endian) $05-$07 : 24-bit Address for Destination Copy. (Big Endian) (From here, Main Data) (Other Data to copy, 8 bytes after the last data, Main Copy Header again and repeats)
ALWAYS DOWNLOADS THIS. It's used for the main part.
Following Data goes to $7EA31D, which then goes to $7EA21D (Check RAM Map)
(Goes to $7FC000, See Item/Schedule Format)
Following Data is Game/Magazine Data. Goes to $400000 or $C00000.