AA00 - data
AA01 - register/command

1A16 - ?
1A4C - latch reg [8]b3 [0]->1->0
1A61 - write a => reg [b]
1A72 - read a <= reg [b]
1A7D - wait for ready?
1A8C - switch RB; a = RB 5 bit
1AAF - write ? RAM?
1AEA - read8? RAM?
1B23 - write? in: reg[4] = b, reg[5] = a, reg[6] = 0x08, reg[7] = 0x00
1B56 - read4? in: reg[4] = b, reg[6] = 0x08, reg[7] = 0x01
1B86 - write? in: reg[4] = b, reg[5] = a, reg[6] = 0x08, reg[7] = 0x02
1BB9 - read4? in: reg[4] = b, reg[6] = 0x08, reg[7] = 0x03
1BE9 - write? in: reg[4] = b, reg[5] = a, reg[6] = 0x08, reg[7] = 0x04
1C1C - read4? in: reg[4] = b, reg[6] = 0x08, reg[7] = 0x05
1C4C - write? in: reg[4] = b, reg[5] = a, reg[6] = 0x08, reg[7] = 0x06
1C7F - read4? in: reg[4] = b, reg[6] = 0x08, reg[7] = 0x07
1CAF - write? reg[6] = 0x04, reg[7] = 0x01
1CC7 - write? reg[6] = 0x04, reg[7] = 0x00
1CDF - write16?
1D51 - read16?
1DD1 - write? reg[6] = 0x05, reg[7] = 0x01
1DE9 - write? reg[6] = 0x05, reg[7] = 0x00
1E01 - delete? call 1DE9; write? reg[6] = 0x05, reg[7] = 0x03; call 1A7D; reg [4] = 0x0F, reg[5] = 0x0F, reg [6] = 6; loop i=0..F reg [7] = i
1E51 - write16?
1EAF - read16?