Here is a list of common operations in Mic-1

• Fetch a byte from the code cache
  PC=PC+1;fetch
• Read a word from the data cache
  MAR=address;rd
wait a cycle for data to appear in MDR
• Write a word to the data cache
  MAR=address
MDR=data;wr
• Pop a value from the stack
  SP=SP-1
• Update TOS
  TOS=new value
• Pop a value and update TOS
  MAR=SP=SP-1;rd
wait a cycle
TOS=MDR
• Fetch a 16-bit signed offset from the code cache
  PC=PC+1;fetch
PC=PC+1;fetch
H=MBR<<8
H=H OR MBRU
• Fetch a 16-bit unsigned offset from the code cache
  PC=PC+1;fetch
PC=PC+1;fetch
H=MBRU<<8
H=H OR MBRU
• Push a word onto the stack
  MAR=SP=SP+1
MDR=value;wr
• Push a word onto the stack and update TOS
  MAR=SP=SP+1
TOS=MDR=value;wr