2. Execution of the program proceeds without an error message but the cash
drawer does not open. There are several possible causes:
A. Consult the documentation for your computer to verify the white wire
to the cash drawer is connected to "Transmit Data" (TxD) and the
black wire is connected to "Signal Ground" (SG).
B. The AC adapter may be defective. Check it with a voltage meter if
possible. It should produce 12 VDC to 18 VDC when measured at the
connector to the cash drawer. The center conductor should be
negative with respect to the outer conductor. (Many replacement
adapters available at electrical supply houses are wired oppositely.) If
a replacement adapter is being used, it should be rated 12 VDC at 300
mA. to 800 mA. Radio Shack part number 273-1652 is acceptable.
However, take care to use the NEGATIVE TIP configuration (meaning
negative is on the inside).
C. The trigger board may be defective. This can be checked by removing
the interface connector from the computer and momentarily
connecting a voltage source (a 9 Volt transistor battery or a 6 Volt
lantern battery). Connect the white wire to the positive terminal and
the black wire to the negative terminal of the battery. (If the polarity is
reversed, no harm will be done.) The cash drawer should open. Make
sure the AC adapter is still connected normally for the test.
If the cash drawer now opens properly using a test program but fails to open using
vendor software for your system, check the following points with the software vendor.
1. The software is sending the data to the correct serial port that the cash
drawer is attached to.
2. The BAUD rate is 300 or slower.
3. If the BAUD rate is faster, the number of characters sent must be increased.
Twenty quickly repeated open commands will operate the drawer at BAUD
rates up to 9600. The best open commands are "@" (ASCII 64), or "BEL"
(ASCII 7).
If the software is incompatible, consider changing the software vendor or upgrading the
interface to the M-S KSI interface.
Installation – Parasite Serial Mode
KC interfaced cash drawers may be used with a serial printer attached to the same
serial port by using a "Y" cable. The cash drawer will open whenever data is sent to the
printer. If independent operation of the printer and cash drawer is required, the M-S
KSI interface should be used. In this configuration handshaking is done by the printer.
The jumpers used in the dedicated serial mode to simulate handshaking are not used.
The white and black wires to the cash drawer are connected as described in the
