Communication Protocol - Datavideo HDR-200 User Manual

4. Communication Protocol

1. All communications between the CONTROLLER and the DEVICE will be under the direct supervision of the
CONTROLLER.
When the DEVICE (HDR-200) receives the COMMAND from CONTROLLER, the following COMMAND is
returned.

ACK:
 COMMAND+DATA:
 NAK+ERROR DATA:
2. The CONTROLLER must not transmit additional COMMAND blocks to a DEVICE (HDR-200) prior to
response to a previous COMMAND block.
3. The CONTROLLER must transmit of bytes in a COMMAND block for with intervals less than 10
milliseconds. If a DEVICE (HDR-200) detects an interruption of a byte in a COMMAND block that exceeds
10 milliseconds, it executes a TIME-OUT error sequence, voids the receiving COMMAND block, and transmit
a NAK (TIME OUT).
4. When a DEVICE (HDR-200) receives a COMMAND block from the CONTROLLER, the DEVICE must
transmit a response within 9 milliseconds. Therefore if the CONTROLLER cannot receive the appropriate
response from the DEVICE within 10 milliseconds after transmitting the COMMAND block the
CONTROLLER detects a communication error, and must execute an appropriate process.
5. When a DEVICE (HDR-200) detects a communication error, it must immediately transmit a NAK to the
CONTROLLER. (The content of an error is shown on the COMMAND tables.) When the CONTROLLER
receives a NAK, if must immediately stop transmission of the block. The DEVICE must not accept a
subsequent command within 10 milliseconds after that (except NAK-UNDEFINED command) and must
execute a necessary process.
5. Command Table (without Checksum byte)
00h 11h : Device Type Request
20h 00h : Stop
20h 01h : Play
20h 02h : Rec
20h 10h : Fast Forward
2xh 13h : Shuttle Forward
21h 13h 00h : Pause
20h 20h : Rewind
2xh 23h : Shuttle Rewind
40h 50h : Increase Track Number
40h 51h : Decrease Track Number
41h 52h nnh: Set Track Number
41h 53h nnh: Select Video Input Source
61h 0Ch 01h : Current Time Sense
61h 20h : Status Sense
E0h 01h : Get Current Track Length
In case that the DEVICE receives a COMMAND not requiring data
In case that the DEVICE receives a COMMAND requiring data
In case that a communication error is detected or an undefined
COMMAND is received
COMMAND
12h 11h 20h 41h NTSC Mode
12h 11h 21h 41h PAL Mode
10h 01h : Acknowledge
10h 01h : Acknowledge
10h 01h : Acknowledge
10h 01h : Acknowledge
10h 01h : Acknowledge
10h 01h : Acknowledge
10h 01h : Acknowledge
10h 01h : Acknowledge
10h 01h : Acknowledge
10h 01h : Acknowledge
10h 01h : Acknowledge
10h 01h : Acknowledge
74h 04h : LTC Time Data
7xh 20h : Status Data
F4h 01h : Track Length
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