CDB6422 Cirrus Logic Inc, CDB6422 Datasheet - Page 7

• Manufacturer Part Number: CDB6422
• Description: Development Kit
• Manufacturer: Cirrus Logic Inc

Specifications of CDB6422

• Silicon Manufacturer: Cirrus Logic
• Application Sub Type: Telephone
• Kit Application Type: Communication & Networking
• Silicon Core Number: CS6422
• Description/function: Audio DSPs
• Operating Supply Voltage: 5 V to 12 V
• Product: Audio Modules
• Kit Contents: Evaluation Board
• Rohs Compliant: No
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With/related Products: CS6422

the phone after this occurs, slide the HOOK
SWITCH first to the "OFF_HOOK" position and
then back to the "ON_HOOK" position.
2.6.2
The default state of the keypad is to generate
DTMF tones when the keys are pressed to enable
dialing through the analog phone network. The
keypad also allows for manual CS6422 register en-
try and CS6422 register configuration storage and
recall in association with the LOAD pushbutton
(SW5). See the description of the LOAD pushbut-
ton for more information.
2.6.3
SW1 contains and 8-position DIP switch which en-
ables access to some commonly-used CS6422 reg-
ister parameters. The operation of the DIP switch
is such that if the DIP switch is moved from the
OPEN state to the CLOSED state, the specified
register is written with the stated contents. For ex-
ample, if switch 1 “MIC=0” is moved from the
OPEN state to the CLOSED state, then the value of
the MIC parameter is set to '0'. When the switch is
moved from the CLOSED state to the OPEN state,
the previous value of the parameter is restored. In
the above example, if Mic were initially '1' when
switch 1 was CLOSED, it would be restored to '1'
when the switch was OPENed.
If the Mic parameter were initially '0' at the time
switch 1 was CLOSED, it would remain '0' when
switch 1 was switched from CLOSED back to
OPEN.
2.6.4
The "6422_RST" pushbutton initiates a COLD
hardware reset on the CS6422 device and down-
loads the register set stored in Configuration 0 to
the CS6422.
DS295DB2
KEYPAD:
DIP SWITCH:
“6422_RST” PUSHBUTTON:
2.6.5
The “LOAD” button changes the state of the KEY-
PAD to enable direct programming of the CS6422
registers and to allow access to the Configuration
sets. Both of these features are particularly useful
when using the CDB6422 in a "stand-alone" envi-
ronment, that is, when the board is not connected to
a PC.
Pressing the “LOAD” button once places the KEY-
PAD in the “LOAD” state (LEDs in status bar turn
off). The 4 following KEYPAD presses encode a
hexadecimal (0000 to ffff) number which the mi-
crocontroller interprets as a CS6422 register write.
Each KEYPAD press causes a pair of LEDs in the
status bar to light. After the fourth keypress, the
hex value is transmitted to the CS6422's uC inter-
face. See the “Register Definition” section of the
CS6422 data sheet.
If the register write is valid (last digit is ‘0’, ‘2’, ‘4’,
‘6’, ‘8’, or ‘a’), then the local copy of the CS6422
registers is updated in the microcontroller. If the
register write is invalid, the register contents are
transmitted to the CS6422, but the microcontrol-
ler's local copy remains unchanged.
After the last digit has been entered, the write takes
effect and the KEYPAD returns to its normal
DTMF state. Furthermore, the LEDs in the status
bar return to display Receive Volume information.
Pressing the “LOAD” button twice in a row places
the KEYPAD in “Configuration Recall” state (2
LEDs in status bar light). The next KEYPAD press
selects a CS6422 register Configuration (0-9) to re-
call. Once selected, the configuration set (all 6 reg-
isters) is transmitted to the CS6422. The KEYPAD
and status LEDs return to their normal states after
the Configuration number has been selected.
Pressing the “LOAD” button three times in a row
places the KEYPAD in “Configuration Save” state
(4 LEDs in status bar light). The next KEYPAD
press stores the current CS6422 register configura-
tion in the selected Configuration location (0-9).
“LOAD” PUSHBUTTON:
CDB6422
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