Question: 1. Why is RAS*-oniy refreshing now less popular than CAS*-before-RAS* refreshing? Why does the CAS*-only refresh make it easy to design a refreshing system?
2. Dynamic memory refresh can be carried out by either hardware or software techniques (in the latter a periodic interrupt or a periodically called procedure causes an access to each column address to carry out the access). What are the advantages and disadvantages of each type of refresh technique?