DirecTV DTV-MD0-0058 User Manual

Page of 49
   
DIRECTV Set-top box information for the installer
 
DIRECTV Proprietary 
 
November 17, 2005 
Version 1.1.a 
Page 12 of 49 
DTV-MD-0058 
Table 7: Passive Drive Characteristics 
Parameter 
Specification 
Output 
-2 mA 
±20% at + 3 volts and –10 mA 
±20% at –5 volts 
 
3.8.3  Low-Speed Signaling Conventions 
The data port signaling conventions will be as listed in Table 8. 
 
Table 8: Low-Speed Data Port Signaling Conventions 
Interchange voltage 
negative or positive 
Binary state 
1 or 0 
Signaling state 
mark or space 
Function 
OFF or ON 
 
The idle state for data port pins two (2) and three (3) will be “mark”. 
3.9  USB 2.0 Data Ports  
 
All new DIRECTV Set-top boxes (STB) have USB 2.0 data ports replacing the DB-9F or RJ22 
data port connectors.  The STB USB port has a host configuration.  USB 2.0 data ports may have 
a default baud rate of 9600 or 115200 in new models.  Serial commands are interfaced through 
the data port using a USB-Serial adapter.  The following RS-232-compatible serial port adapters 
will be supported: 
 
 
Manufacturer 
Model 
USB Vendor 
ID 
USB Product 
ID 
IOGEAR GUC232A 
0x067B  0x2303 
ATEN UC-232A  0x067B 0x2303 
BAFO BF-810 
0x067B 0x2303