Multi-Tuner Data Port Commands; Default Data Rate And Format; Command Protocol; Table 4-4: Multi-Tuner Commands Summary - DirecTV D10 Installation Manual

DIRECTV Set-Top Box Information for the Installer

4.4 Multi-Tuner Data Port Commands

A new set of commands are introduced for multi-tuner STBs, such as R15 and HR20. For multi-tuner
STBs, the tuner needs to be identified for many of the commands as an input parameter. To maintain
backward compatibility, new commands with the suffix "MT", have been created that have a TunerID
parameter added. In the case where an original non TunerID command is issued to a multi-tuner STB,
it will be executed as the equivalent "MT" command with TunerID set to 0x01. The [TunerID] shall
start at 0x01 and increase in value by one for each additional tuner (i.e. 0x01, 0x02, 0x03...). The
[TunerID] can be obtained by issuing the command GetTuner. See Table 4-1 for the list of STBs that
support the multi-tuner commands.
Comman
Command Label
d Code
0x9A GetTuner
0x8A GetPrimaryStatusMT
0x8B GetCurrentChannelMT Get the major and minor numbers of the tuned channel.
0x9D GetSignalQualityMT
0x9F OpenUserChannelMT

4.5 Default Data Rate and Format

All STBs have a default data rate of 9600. The data format is 1 start bit, 8 data bits, no parity, 1 stop
bit, and no handshaking.

4.6 Command Protocol

The STB will use the command and data acknowledgment protocol for flow control as specified in
Figure 4-1.
Any controller that is implemented to control DIRECTV STB, should follow the protocol depicted in
Figure 4-1.
DIRECTV, Inc.
Version 2.2

Table 4-4: Multi-Tuner Commands Summary

Get the number of tuners and their designations.
Get the status information of current channel.
Get the signal level for the tuned channel.
Tune to a channel by inputting a channel number.
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Description
March 5, 2008
DTV-MD-0058