ASI4U datasheet(27/71 Pages) RENESAS

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ASI4U / ASI4U-E / ASI4U-F Datasheet

January 26, 2016

The Addressing Channel generally becomes deactivated by an IC reset.

If the IC is locked to the Addressing Channel and AC Current Input Mode (see descriptions further below) is

active, there are four special IC functions that are implemented to support existing handheld programming

devices (from the company Pepperl+Fuchs):

The IC does not leave the Addressing Channel Mode after the reception of a Reset_Slave or

Broadcast_Reset call if the Data_Exchange_Disable flag is cleared (0). This is always the case if the

ASI4U/ASI4U-E/ASI4U-F has performed data or parameter communication before the reset so that the

handheld has been operating in Data or Parameter Mode.

The IC does not leave the Addressing Channel during an IC reset that was caused by an expired

Communication Watchdog.

See section 4.15 for detailed descriptions of the Communication Monitor and Communication Watchdog.

Software controlled IC resets (resets through Reset_Slave or Broadcast_Reset calls) are performed

slightly differently than resets in normal slave IC operation.

The IC still resets the data and parameter outputs immediately after reception of the calls, and Data

Strobe and Parameter Strobe signals are generated. However, the IC initialization procedure is

postponed for 2.048ms (-6.25%), keeping the IC blocked to any further telegram inputs at the Addressing

Channel or the AS-i line input. This is to avoid an immediate reactivation of the Addressing Channel after

IC initialization since the handheld programming device always sends five subsequent Broadcast_Reset

calls. The ASI4U would otherwise process the first reset call from the handheld correctly but misinterpret

the four remaining calls as a new Magic Sequence.

The UART is constantly set to Synchronous Receive Mode. This is because the signal sequence that is

generated by the handheld programming device exhibits an additional signal transition in a time frame of

3 bit-times after the end of the transmitted master call.

ASI4U bảng dữ liệu(PDF) 27 Page - Renesas Technology Corp