This is a Flash image for the Suska-IV-B and Suska-IV-BF boards.
The different operating systems are located as follows 
(an IP-core with appropriate CPU is required):

Address switch 0000 : empty               ; address offset 0x000000. B-board
Address switch 0001 : empty               ; address offset 0x080000. B-board
Address switch 0010 : tos162de            ; address offset 0x100000. B-board
Address switch 0011 : tos162uk            ; address offset 0x180000. B-board
Address switch 0100 : tos206de            ; address offset 0x200000. B-board
Address switch 0101 : tos206uk            ; address offset 0x280000. B-board
Address switch 0110 : tos306bf            ; address offset 0x300000. B-board
Address switch 0111 : tos404bf            ; address offset 0x380000. B-board (boot from Gigafile, needs MMU)
Address switch 1000 : etos140             ; address offset 0x400000. B-board
Address switch 1001 : tos404bf-68k30l.img ; address offset 0x480000. B-board (boot from Gigafile, no MMU needed)
Address switch 1010 : empty               ; address offset 0x500000. B-board
Address switch 1011 : empty               ; address offset 0x580000. B-board
Address switch 1100 : empty               ; address offset 0x600000. B-board
Address switch 1101 : etoscurr            ; address offset 0x680000. B-board
Address switch 1110 : etosdebug           ; address offset 0x700000. B-board
Address switch 1111 : etoscli             ; address offset 0x780000. B-board

The Flash image features also cartridge support for the cartridge address 
space 0xfa0000 to 0xfaffff at the following addresses:
0x040000 to 0x04ffff
0x0c0000 to 0x0cffff
0x140000 to 0x14ffff
0x1c0000 to 0x1cffff
0x240000 to 0x24ffff
0x2c0000 to 0x2cffff
0x340000 to 0x34ffff
0x3c0000 to 0x3cffff
0x440000 to 0x44ffff
0x4c0000 to 0x4cffff
0x540000 to 0x54ffff
0x5c0000 to 0x5cffff
0x640000 to 0x64ffff
0x6c0000 to 0x6cffff
0x740000 to 0x64ffff
0x7c0000 to 0x6cffff

The Flash image features also cartridge support for the cartridge address 
space 0xfb0000 to 0xfbffff at the following addresses:
0x050000 to 0x05ffff
0x0d0000 to 0x0dffff
0x150000 to 0x15ffff
0x1d0000 to 0x1dffff
0x250000 to 0x25ffff
0x2d0000 to 0x2dffff
0x350000 to 0x35ffff
0x3d0000 to 0x3dffff
0x450000 to 0x45ffff
0x4d0000 to 0x4dffff
0x550000 to 0x55ffff
0x5d0000 to 0x5dffff
0x650000 to 0x65ffff
0x6d0000 to 0x6dffff
0x750000 to 0x65ffff
0x7d0000 to 0x6dffff

The Flash image features also cartridge support for the cartridge address 
space 0xfc0000 to 0xfcffff at the following addresses:
0x060000 to 0x06ffff
0x0e0000 to 0x0effff
0x160000 to 0x16ffff
0x1e0000 to 0x1effff
0x260000 to 0x26ffff
0x2e0000 to 0x2effff
0x360000 to 0x36ffff
0x3e0000 to 0x3effff
0x460000 to 0x46ffff
0x4e0000 to 0x4effff
0x560000 to 0x56ffff
0x5e0000 to 0x5effff
0x660000 to 0x66ffff
0x6e0000 to 0x6effff
0x760000 to 0x66ffff
0x7e0000 to 0x6effff

The Flash image features also cartridge support for the cartridge address 
space 0xfd0000 to 0xfdffff at the following addresses:
0x070000 to 0x07ffff
0x0f0000 to 0x0fffff
0x170000 to 0x17ffff
0x1f0000 to 0x1fffff
0x270000 to 0x27ffff
0x2f0000 to 0x2fffff
0x370000 to 0x37ffff
0x3f0000 to 0x3fffff
0x470000 to 0x47ffff
0x4f0000 to 0x4fffff
0x570000 to 0x57ffff
0x5f0000 to 0x5fffff
0x670000 to 0x67ffff
0x6f0000 to 0x6fffff
0x770000 to 0x67ffff
0x7f0000 to 0x6fffff