Compact FLASH III Digital Audio System
Copyright©1992-2007 by ACS, Sarasota, Florida
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ALL RIGHTS RESERVED
Upgrading the Firmware
The CFSound-III is designed to be field-upgradeable. The firmware that controls the unit s operation
may be upgraded in the field with new versions to add features or functionality, or to correct problems.
The process requires a PC running Windows with an available serial port. A USB serial port may or
may not work depending upon how well the device s driver was written. ACS recommends using a
conventional serial port if possible.
The unit is connected to the programming PC with a one-to-one DB9 Male/Female 9-pin serial cable
and gender changer. These are available at CablesOnline:
http://cablesonline.stores.yahoo.net/69wirdb9mfex.html
http://cablesonline.stores.yahoo.net/db9femslimge.html
As an alternative, a cable may be constructed with a pair of DB9 Female solder cup connectors and
three wires:
Note that this same cable may be used to view the CFSound-III s power-up diagnostic messages,
which includes the current firmware version, by using Window s Hyperterminal accessory on the PC
configured to 2400 baud, 8 data bits, 1 stop bit, no flow control. CFSound jumper block JB2 provides a
Null Modem capability to swap the RxD and TxD signals by rotating the pair of jumpers 90 degrees.
The CFSound-III case must be opened to allow access to the BOOT jumpers. Two screws on the
bottom of the unit allow the case to be opened.
The BOOT jumpers determine whether the CFSound-III starts running from Flash memory (installed)
or from a small bootstrap EEProm (uninstalled).
The sequence of steps in the following table outlines the firmware upgrade process.