BOB-II is Decade's second-generation low-cost videotext overlay module. BOB-II lets your microcontroller or PC display up to 308 characters on standard video monitors and TV sets. BOB-II generates video on-board, or automatically genlocks to your video source and superimposes text on the image. Printable characters and commands control BOB-II through a fast RS-232 style data link, much like a simple serial printer. BOB-II is compatible with virtually all microcontroller chips and modules, including the BASIC Stamptm. Single units sell for $99.95 (NTSC or PAL), with a matching 30-pin socket and brownout detector IC.
END OF LIFE notice: For BOB-II design migration, please see BOB-4.
See also BNAB-GP, Decade's general purpose host adapter board for BOB-II.
Differences: BOB-II vs. BOB-I
|Remote Video Inspection & Test||Industrial Process Monitor|
|Scientific Experiment Monitor||Home Automation|
|Remotely Piloted Vehicles||Robotics|
|Teleoperated Mechanisms||MATV ~ Pay TV|
|CCTV Security & Surveillance||Electronic Signs|
|System Status Display||ATV ~ Amateur TV|
|R/C Models||Law Enforcement|
30-pin SIMM form factor, 3.50(L) x 1.05(W) x 0.35(H), weight is less than 0.5oz. BOB-II snaps into commonly available 30-pin SIMM sockets. A matching socket is supplied in the standard retail package.
+8~16V nominal, 65mA typical current. Auxiliary +5V regulated output rated at 50mA and ±5% tolerance. Auxiliary supply output current adds to main supply current.
Asynchronous serial input at 2400, 4800, 9600, or 19.2Kbps, 8 data bits, no parity, 1 stop bit (8N1), inverted data, 5V logic levels. Connects directly to the UART transmit output pin of any 3~5V microcontroller. An inverting RS-232 interface is required for connection to a PC COM port (can use a single transistorsee BOB-II FAQ). Any standard terminal program (e.g. HyperTerminal) provides basic control of BOB-II directly from a PC keyboard.
RS-170A (NTSC) composite, 1Vpp 75 Ohm unbalanced input and output. PAL video compatibility is optional at ordering time. The video output contains a small (+1V) DC bias, which is common to many video sources and well-tolerated at the inputs to most video equipment. Internal color video background signal is automatically generated if video input is not supplied. Composite sync output is provided.
12x18 pixel bitmaps. Up to 308 characters may be displayed, in 28 columns and 11 rows. 128 character patterns provided, including upper & lower case, European language support, and a set of graphics characters useful for bar graphs, etc. Non-ASCII characters are accessible through a simple command protocol. Default characters are displayed in white with a thin black outline, for best visibility against underlying image content.
Character Display Options:
Character color is supported in local video generation mode. Blinking may be selected for any character or group. Monochrome text (only) is available in genlock-overlay mode. External adjustment of transparency as well as character and screen brightness is optional. Entire text display may be toggled on/off without affecting contents of display RAM. Writes to display RAM are permitted while the display is off.
Product specifications are subject to change without notice. Contact Decade Engineering to confirm current status if any specification is critical to your application.
BOB-II Pinout (PDF) Describes the function of every pin, but you have to connect only a few...
BOB-II Control Protocol (PDF) or, "How do I talk to this thing?"
BOB-II Character Set (PDF) Shows all 128 ROM character patterns.
BOB-II FAQ (PDF) Essential information for anyone developing a BOB-II application. Includes a short snip of MS QuickBASIC code for testing or demonstrating BOB-II with a PC.
BOB-II Application Examples
Vertical Bar Graph (PDF) A well-written example by Al Williams, using the Parallax BASIC Stamp II.
HyperTerminal configuration file example for BOB-II. Just double-click after downloading.
TV Typewriter (TXT) 68HC705 assembly language program and wiring diagram (PDF). Uses standard PC/AT keyboard.
Time/Date Display (TXT) For the PIC16F84 and Philips' PCF8583 RTC (Real-Time Clock) chip. Written in MicroEngineering Labs' PICBasic Pro compiler language.
GPS Data Overlay Code Example (Text) Uses BOB-II with a Parallax BASIC Stamp II and a GPS receiver to superimpose time and position information on video. This application was written by an early BOB-II customer in Guam. A full project description appeared in the Summer 1998 issue of Amateur Television Quarterly magazine.
HVW Technologies, a Canadian dealer for BOB-II modules, also offers an application software example for the Parallax BASIC Stamp II.