MAGNETIC DISC DEVICE

PURPOSE:To confirm recorded data without latency after data write by providing a recording head and a reading head side by side. CONSTITUTION:Write data is transferred to this magnetic disc device through an interface part 7. Thereafter, write data is not only written on a recording surface through a data path 9, a write control part 10 and a writing part 11 but also stored in a data comparing part 15. Data written on the recording surface is read out just after write by a reading part 12 and a read control part 13 and is sent to the data comparing part 15. The data comparing part 15 compares write data and read data; and if they do not coincide with each other, the comparing part 15 reports abnormality to a connecting part 8 through a comparison signal 16. Thus, a host device recognizes immediately abnormality of write.