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WriteTxt TBD.
Warning
Warning frame is the warning message that MPD initiatively sends out to the monitoring program. There
are two cases, one is wrong command report, and the other is operation status report. The monitoring
program does not need to send out acknowledge frame in both cases.
Wrong command report
When MPD sends out wrong command report, it means that MPD has received a non-analysable report
from the monitoring frame. The definitions of related bit field in the wrong command report are as
follows:
LENH=0x00, LENL=0x02: means its data segment length is 1 byte.
WARN=0x22: means it is a warning frame.
DATA[0]=0xBD: means it is a wrong command report.
Operation Status Report
When MPD tests any status change, it will initiatively send out corresponding report to the monitoring
program. The definitions of related bit field in the operation status report are as follows:
LENH=0x00, LENL=0x05: means its data segment length is 4 bytes.
WARN=0x22: means it is a warning frame.
DATA[0..3]: forms a 4-byte status change bit field. Please refer to the Table below for its definition.
Status change bit field
DATA[3] DATA[2]
Bit31..24 Bit23..19 Bit18 Bit17 Bit16
RES RES AUD1 AUD0 VID
DATA[1] DATA[0]
Bit15..10 Bit9 Bit8 Bit7..3 Bit2 Bit1 Bit0
RES PSI TS RES AS PL TVMD
1) RES is always 0;
2) If some bit is 1, it means the corresponding status changes; if it is 0, it means the corresponding status has not
changed.
3) TVMD: Format of analog video output;
4) PL: Syntax byte and level of digital video;
5) AS
：
Audio sampling rate;
6) TS
：
Bit stream status of ASI input;
7) PSI
：
Bit stream PSI information;
8) VID
：
video decode module abnormal;
9) AUD0
：
Audio channel 0 decode abnormal;
10) AUD1: Audio channel 1 decode abnormal.
Handshake Acknowledge Time Order
Handshake Acknowledge rules is given as:

Expect for warning, MPD does not initiatively send out acknowledge data frame, and only when
Host sends out one command, MPD replies with one acknowledge data frame;

Host should send out commands at an interval of more than 50ms;