Zilog Z-80 Cpu 
   8 bit microprocessor 
   16 address lines 
   8 data lines
   4 Mhz Processor 
   Clock Cycles per second = 0.145
   
Motorola 6809 
   8 bit microprocessor 
   16 address lines
   8 data lines 
   1 MHZ Processor 
   Clock cycles per second = 0.420 
MOS Technology 6502 
   8 bit microprocessor 
   16 address lines
   8 data lines
   1 MHZ Processor 
   Clock cycles per second = 0.430 
How do you know if a CPU is an 8 bit or 16 bit? by counting the data lines or address lines? if you didn't have the data sheets or the internet to look it up, how would you know by looking at the schematic?
Is it true if you know the Microprocessors speed you can get the byte/bit rate? 
You take the inversion of the frequency and get the time
1 MHZ  = 0.001 milliseconds
4 MHZ = 0.00025 Milliseconds 
For a 1 Mhz CPU , the bit rate is 0.001 milliseconds?
For a 4 Mhz CPU, the bit rate is 0.00025 milliseconds?
What other common CPUs did arcade games use in the 80's?
1.)  Zilog Z-80 Cpu 
2.) Motorola 6809 
3.) MOS Technology 6502 
4.) Which other ones did they use please?