Scanner Interface; Bluetooth - Intermec CK30 Service Manual

Chapter 4 — Theory of Operation

Scanner Interface

Bluetooth

90
Full handshaking is supported, except for RI (Ring Indicate). This was left
out in anticipation of some DB9 cables supplying +5V, instead of RI, on
DSub pin 9.
U23 and its charge pumps are left on while the CK30 is on, but it draws
very little current with no RS-232 device attached. It is shut off during
Suspend by the DOCK_EN signal from HCR register U11. The
MAX3244 AutoShutdown mode is not used because it doesn't wake up
and restore RS-232 level conversion fast enough if the CK30 suddenly
starts transmitting, causing data corruption.
U23's CD_WAKE output is always active, even when U23 is shut down
during Suspend. This allows the RS-232 DCD* signal to propagate
through U23 and wake the system if it is docked with an active RS-232
device. (This feature is not supported in the current software.)
A full set of scanner interface signals is available on 26-pin docking
connector J13. This is intended for support of "pick and run" applications,
in which the CK30 may be docked in a vehicle dock that has a decoded or
undecoded tethered scanner plugged in. It may also be used for Specials
applications needing to support an internal and a tethered scanner. See
"Tethered Scanner Support Through Dock Connector" on page 85 for
details.
Regulated 5V power is provided through the dock connector for powering
tethered scanners. This power is switched through high-side switch U13,
controlled by the DOCK_EN signals from HCR register U11. This 5V
power is normally powered off and the RS-232 chip disabled during
Suspend, and is automatically shut off in hardware if the main battery is
critically low or removed.
A Class 2 Bluetooth link is supported through an optional module that
plugs into Bluetooth connector J8. (A duplicate set of connector pads, J6,
is provided for future support of larger Bluetooth modules.) The module
includes its own chip antenna.
The Bluetooth module is powered through FET Q9. Software normally
drives control signal BT_PWR_EN* high (off) during Suspend for power
savings. In future software releases, the Bluetooth module may optionally
be left powered during Suspend to support system wakeup from an
incoming Bluetooth message. Bluetooth power is automatically shut off in
a critical battery situation by the "Type 1" interlock mechanism described
in "Device Power Control" on page 58.
CK30 Handheld Computer Service Manual