M93C86 datasheet(18/38 Pages) STMICROELECTRONICS

18 / 38 page

READY/BUSY status

M93C86, M93C76, M93C66, M93C56, M93C46

18/38

READY/BUSY status

While the Write or Erase cycle is underway, for a WRITE, ERASE, WRAL or ERAL

instruction, the Busy signal (Q=0) is returned whenever Chip Select input (S) is driven high.

(Please note, though, that there is an initial delay, of tSLSH, before this status information

becomes available). In this state, the M93Cx6 ignores any data on the bus. When the Write

cycle is completed, and Chip Select Input (S) is driven high, the Ready signal (Q=1)

indicates that the M93Cx6 is ready to receive the next instruction. Serial Data Output (Q)

remains set to 1 until the Chip Select Input (S) is brought low or until a new start bit is

decoded.

Initial delivery state

The device is delivered with all bits in the memory array set to 1 (each byte contains FFh).

Common I/O operation

Serial Data Output (Q) and Serial Data Input (D) can be connected together, through a

current limiting resistor, to form a common, single-wire data bus. Some precautions must be

taken when operating the memory in this way, mostly to prevent a short circuit current from

flowing when the last address bit (A0) clashes with the first data bit on Serial Data Output

(Q). Please see the application note AN394 for details.

M93C86 Datasheet(PDF) 18 Page - STMicroelectronics