ASI4UC-G1-MT ZMDI, ASI4UC-G1-MT Datasheet - Page 50

• Manufacturer Part Number: ASI4UC-G1-MT
• Description: Interface - Specialized ASI
• Manufacturer: ZMDI

Specifications of ASI4UC-G1-MT

• Product Category: Interface - Specialized
• Rohs: yes
• Product Type: Actuator Sensor Interface IC
• Operating Supply Voltage: 16 V to 33.1 V
• Supply Current: 6 mA
• Maximum Power Dissipation: 850 mW
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: SSOP-28
• Minimum Operating Temperature: - 25 C

3.12. UART
The UART performs a syntactical and timing wise analysis of the received telegrams at both telegram input
channels (AS-i input, Addressing Channel input), converts the pulse coded AS-i input signal into a
Manchester-II-coded bit stream and provides the Receive Register with decoded telegram bits.
The UART also realizes the Manchester-II-coding of a slave answer (Slave Mode only) and controls the
telegram data paths at the different operational modes of the IC (Slave Mode, Master Mode, Repeater Mode,
Monitor Mode).
In Slave Mode data communication takes place on the AS-i input and AS-i output ports (AS-i receiver + AS-i
transmitter) by default. The Addressing channel (IRD input + LED1 output) can be activated by a Magic
Sequence sent to the IRD input (see chapter 3.3 Addressing Channel Input IRD). If the Addressing Channel is
activated, the AS-i channel is turned inactive. Re-activation of the AS-i channel requires a reset of the IC.
In Master-, Repeater- and Monitor Mode the output signal of the manchester coder (AS-i pulse to MAN signal
conversion) is resynchronized and forwarded to pin LED1. Any pulse timing jitters of the received AS-i signal
become removed, as long as they stay within the specified maximum limits. If the received AS-i telegram does
not pass one of the different error checks (see detailed description below), the LED1 output is distorted in
such a way that it will not form any AS-i telegram signal anymore.
In Master-, Repeater- and Monitor Mode the ASI4U provides a simple interface function between AS-i channel
and Addressing Channel. The channel receiving an input signal first while the UART is in idle state (no active
communication) is activated and locked until a communication pause is detected on that channel.
3.12.1.
The comparator stages at the AS-i-line receiver generate two pulse-coded output signals (p_pulse, n_pulse)
disjoining the positive and negative telegram pulses for further processing. To reduce UART sensitivity on
erroneous spike pulses, pulse filters suppress any p_pulse, n_pulse activity of less than 750 ns width.
After filtering, the p_pulse and n_pulse signals are checked in accordance with the AS-i Complete
Specification for following telegram transmission errors:
Start_bit_error
Alternating_error
Timing_error
No_information_error
Data Sheet
January 30, 2012
ASI4U / ASI4U-E
Spec. 3.0 Com
AS- i input channel
© 2012 Zentrum Mikroelektronik Dresden AG — Rev. 2.1
All rights reserved. The material contained herein may not be reproduced, adapted, merged, translated, stored, or used without
the prior written consent of the copyright owner. The information furnished in this publication is PRELIMINARY and subject to
changes without notice.
pliant Universal AS-I IC
The initial pulse following a pause must have negative polarity. Violation of this rule
is detected as Start_bit_error. The first pulse is the reference for bit decoding. The
first bit detected shall be of the value 0.
Two consecutive pulses must have different polarity. Violation of this rule is detected
as Alternating_error.
Note: A negative pulse shall be followed by a positive pulse and vice versa.
Within any master request or slave response, the digital pulses that are generated
by the receiver are checked to start in periods of
initial negative pulse, where n = 1 ... 26 for a master request and n = 1 ... 12 for a
slave response. Violation of this rule is detected as Timing_error.
Note: There is a certain pulse timing jitter associated with the receiver output signals
(compared to the analog signal waveform) due to sampling and offset effects at the
comparator stages.
In order to take the jitter effects into account, the timing tolerance specifications
differ slightly from the definitions of the AS-i Complete Specification.
Derived from the Manchester-II-Coding rule, either a positive or negative pulse shall
be detected in periods of
where n = 1 ... 13 for a master request and n = 1 ... 6 for a slave response. Violation
of this rule is detected as No_information_error.
Note: The timing specification relates to the receiver comparator output signals.
There is a certain pulse timing jitter in the digital output signals (compared to the
analog signal waveform) due to sampling and offset effects at the comparator
stages.
(
n
*
6

s
)


. 1
. 0
500
875


s
s
after the start of the initial negative pulse,
(
n
*
3

s
)


. 1
. 0
500
875


s
s
after the start of the
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