This is a testprogram to verify the correct mapping of the GMod3 cartridge.

to be able to identify the ROM pages easily, flash the cartridge using the
"flash-markbanks" program first.

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00 00 00 cc 37                          
00 00                                   
                                        
00 2f 37 01 01 01 01 01 01 01 01        
10 01 01 01 01 01 01 01 01 01 01        
20 01 01 01 01 01 01 01 01 01 01        
30 01 01 01 01 01 01 01 01 01 01        
40 01 01 01 01 01 01 01 01 01 01        
50 01 01 01 01 01 01 01 01 01 01        
60 01 01 01 01 01 01 01 01 01 01        
70 01 01 01 01 01 01 01 01 01 01        
80 00 00 ff ff ff ff ff ff ff ff        
90 ff ff ff ff ff ff ff ff ff ff        
a0 94 e3 7b e3 43 42 4d 42 41 53        
b0 bf b1 a5 65 45 0b 25 08 45 0b        
c0 01 01 01 01 01 01 01 01 01 01        
d0 10 10 10 10 10 10 10 10 10 10        
e0 85 56 20 0f bc a5 61 c9 88 90        
f0 dd 09 02 8d 01 dd 2c 01 dd 70        
ff 42 59 43 fe e2 fc 48 ff              
--------------------------------------------------------------------------------

first line:
- high byte of ROM bank
- low byte of ROM ban
- value written to control byte
- ghostbyte at $ffff (RAM)
- value written to $01 (CPU port, memory config)

second line:
- high byte of ROM bank (read back from register)
- low byte of ROM bank (read back from register)

following lines are read from memory at $0000, $1000, $2000 etc. 

the last line is read from $fff8, so it contains the hardware vectors. toggling 
the hw-vectors should not have any effect on the rest of the mapping.

at the bottom there is a bit of "graphics" that is located in the RAM at $f800
(charset) and $fc00 (videoram) respectively. also the border is opened to show
the ghostbyte at $ffff. none of it should change when enabling/disabling the
cartridge ROM or the hw-vectors.

the two rasterbars at the top are showing the active NMI and IRQ vectors:

the top bar is generated by timer NMI,
- red means the vector in RAM is active
- orange means the vector in kernal ROM is active
- green means the vector in cartridge ROM is active

the bottom bar is generated by raster IRQ,
- red means the vector in RAM is active
- yellow means the vector in kernal ROM is active
- green means the vector in cartridge ROM is active

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keys:

Q and W     increment/decrement the ROM bank number
A and S     increment/decrement the memory config
E           toggle bitbank mode (should have no effect in this program)
R           toggle EXROM line (toggles cartridge ROM on/off)
T           toggle hardware vectors (pattern from cartridge ROM or from Kernal)
D           shift ROM bank number left (multiplay by two)