CDB61581 Datasheet, PDF (7/16 Pages) Cirrus Logic – Universal Line Interface Unit

CDB61581
11. CDB61581 SOFTWARE
The CDB61581 can be configured in the host/soft-
ware mode using the application CDB61581.EXE
supplied with the board. This application allows the
user to access all of the user programmable regis-
ters in the device. It runs under Windows 95 and
98.
11.1. Configure PC
This function allows the user to set the address of
the PC parallel port. The selection depends on the
configuration of the user’s PC. The Plug and Play
(PnP) function of the operating system determines
this address every time the PC is powered up, but it
normally won’t change the printer port address un-
less the configuration of the hardware has changed
since the PC was last powered up. There are two
ways to determine the address of the parallel port:
the safe method and the fast method.
The safe method is to double click on the My Com-
puter icon on the desktop, double click on Control
panel, then Double click on System. Select the De-
vice Manager tab, then with “View devices by
type” selected in the window that pops up, double
click on Ports (COM & LPT). Click on the Printer
Port icon that corresponds to the port that is con-
nected to the CDB61581 evaluation board, then se-
lect Properties. On the Properties window, select
the Resources tab, then read the I/O address in the
Input/Output Range field. This is the address range
to select for the CDB61581.
The fast method is to try the ports one by one, going
to the Configure Part window every time to see
which one allows the user to read from the device.
when the wrong address is selected, the bit fields in
this window will read either all zeroes or all ones.
Going to the Configure Part window automatically
issues a read command to the device, which will
cause unpredictable results if the selected LPT port
is connected to some device other than a
CDB61581 evaluation board. Before using this
method, the user is advised to disconnect all other
devices from the LPT ports.
11.2. Configure Part
Clicking on Configure_Part brings up two options:
the first is Control Register Configuration, which
gives access to the control and status registers, and
Transmitter RAM Configuration, which configures
the Arbitrary Waveform Generator (AWG). See
the CS61581 datasheet for information on pro-
gramming these registers.
11.3. Control Register Configuration
Selecting Control Register Configuration pulls up
the register configuration window and automatical-
ly issues a read command to the CDB61581. The
user must make sure that the software is configured
to use the proper LPT port before this option is se-
lected (see Configure PC above).
The register configuration window is shown in
Figure 1. The bits in the Control Registers (CNTL
REG 1, CNTL REG 2, CNTL REG 3) are written
by checking the box opposite to the individual bits
in the "Write" columns, then clicking on the "Write
Registers" button. This writes the displayed data to
all three control registers, then automatically reads
the control and status registers and displays the re-
sults in the "Read" columns. Since Control Register
1 is effectively a control register when it is written
and a status register when it is read, the read status
is decoded and displayed in the Read Status win-
dow.
The registers can also be read by clicking on the
"Read Registers" button. All five registers are read
when this command is selected.
The LATN REG register shows the current setting
of the gain-equalizer. The QRSS DPEC register
displays the number of bit errors while receiving a
QRSS pattern.
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