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