D
E C A D E
E
N G I N E E R I N G
5504 ValView Dr. SE, Turner, OR 97392-9517 (USA) ~
tel:
503.743.3194 ~
fax:
503.743.2095
website:
www.decadenet.com
BOB-3 Application Guide ~ Firmware V3.4 ~ December 21, 2004
(
Please check our website for the latest version of this document.
)
Introduction
BOB-3 is Decade's third-generation low-cost videotext overlay module. BOB-3 lets your microcontroller or PC
display up to 680 characters on standard video monitors and TV sets. With 63 user-definable characters, BOB-3
supports pseudo-graphics and multiple languages. BOB-3 generates video on-board, or automatically genlocks to
your video source and superimposes characters over the image. Printable characters and commands control BOB-
3 through a fast RS-232 style data link, much like a simple serial printer. BOB-3 works with most microcontroller
chips and modules, including the BASIC Stamp
tm
. PAL video compatibility is optional at ordering time.
Cautions & Revision History
ESD (electro-static discharge) safety precautions must be followed at all times when handling BOB-3 modules. Use
a grounded wrist strap and grounded work surface. BOB-3 modules must be stored and shipped in static-shield
(metallic, not pink poly) packaging. Use a SIMM socket! Soldering directly to BOB-3 voids the warranty.
[V3.40]
Fixed bugs: BE command repetition eventually trashes display, video status ignored during vertical scroll.
Allowed printing outside active vertical scroll block. Revised vertical scroll behavior to print incoming characters
immediately instead of waiting for line buffer full or <CR>. Added simple ‘networking’ support on pin 6. Added 2C
and 2L commands, to support <LF> code.
[V3.30]
Fixed bugs: RAM characters sometimes invisible after video mode change, JN command fails if new value
is less than current line number. Allowed arbitrary data with Y command in boot script. Disabled P command
execution in boot script. Added hardware method to clear boot script. Supported double-width characters in text
crawl. Added work-around for minor artifact of JO command.
[V3.20]
Fixed minor bugs in H command processors. Added PAL range limits for H commands and corrected the
list of supported ASCII codes in this document.
[V3.10]
The status report string was further extended in firmware version 3.10, to include video standards
compatibility reporting (NTSC or PAL). See S command description.
[V3.00]
Several commands were added or extended. The new commands are: JR, K, MI, MN, VL, Y, ZC, ZP, 1D
and 1S. Boot script capacity (N command) was doubled, and three new communication bit rates were added. All
changes are believed to be backward compatible with version 2 application programs except increased start-up
delay time (to 500mS), a different report string generated in response to the S command, and the (simplified)
response to bad commands.
[V2.00]
N command termination character was changed from <CR> to”|” (the vertical bar symbol).
BOB-3 Version 3.4 Application Guide ~ Copyright © 2004 by Decade Engineering ~ Page 1
