Semiconductor integrated circuit and data processing system
View Patent ↗To enhance the speed of first access (read access different in word line from the previous access) to a multi-bank memory, multi-bank memory macro structures are used. Data are held in a sense amplifier for every memory bank. When access is hit to the held data, data latched by the sense amplifier are output to thereby enhance the speed of first access to the memory macro structures. Namely, each memory bank is made to function as a sense amplifier cache. To enhance the hit ratio of such a sense amplifier cache more greatly, an access controller self-prefetches the next address (an address to which a predetermined offset has been added) after access to a memory macro structure so that data in the self-prefetched address are preread by a sense amplifier in another memory bank.
1. A semiconductor circuit comprising:
a memory block having a first access port, a second access port, an address alignment circuit, and a memory circuit;
a first circuit block accessing the memory circuit via the first access port; and
a second circuit block accessing the memory circuit via the second access port;
wherein the address alignment circuit is coupled to the first and second ports, and the bit alignment of an address signal is changed by the address align circuit to a first bit alignment or a second bit alignment according to information set in a control register, the address signal being inputted from the first and second circuit blocks via the first or second access ports.
2. A semiconductor circuit according to claim 1 ,
wherein the first circuit block is a CPU, and
wherein the CPU sets the information into the control register.
3. A semiconductor circuit according to claim 2 ,
wherein the second circuit block is an external bus interface circuit.
4. A semiconductor circuit according to claim 1 ,
wherein the memory circuit has a plurality of memory banks,
wherein when the first circuit block accesses one of the plurality of memory banks, the second circuit block can access another one of the plurality of memory banks.
5. A semiconductor circuit according to claim 4 ,
wherein when the first circuit block and the second circuit block access the same one of the memory banks, the first circuit block has priority over the second circuit block.
6. A semiconductor circuit according to claim 4 ,
wherein each of the plurality of memory banks has a plurality of dynamic type memory cells.