ZEPIR0BAS02MODG datasheet(21/78 Pages) ZILOG

21 / 78 page

PS030504-0917

Serial Interface Mode

ZMOTION® Detection Module II

Product Specification

Write Command Structure

Write commands are used to update the configuration of ZDMII, and are sent from the

Host. The Module responds with the current value as an acknowledgment. The Host then

sends the new data and the Module responds with an ACK.

• All write commands are initiated by single upper-case letters.

• After a write command is received, the device returns the current value and expects an

appropriate single-byte data value.

• When the data value is received, the device returns an ACK. If no data is received after

the inactivity time-out period of 2.5 seconds, the device returns a NACK. See the ex-

ample in Figure 6.

Confirmed Command Structure

Certain commands require a specific sequence of characters to be sent to prevent acciden-

tal initiation. These commands require a 4-character confirmation sequence. After a com-

mand requiring confirmation is received, the device returns an ACK.

• If the sequence is correct, the device returns an ACK and executes the command.

• If the sequence is incorrect, or if there is an inactivity delay of more than 2.5 seconds

between any characters of the sequence, the device immediately sends a NACK and

does not execute the command. See the example in Figure 7.

Figure 6. Write Command Structure

Command

Current Value

New Value

ACK

Host

ZDM II Module

ZEPIR0BAS02MODG Datasheet(PDF) 21 Page - Zilog, Inc.