T8536B ETC-unknow, T8536B Datasheet - Page 23

• Manufacturer Part Number: T8536B
• Description: T8535b/t8536b Quad Programmable Codec
• Manufacturer: ETC-unknow

September 2001
Agere Systems Inc.
Functional Description
The Control Interface
Write All Channels
The write all channels command causes all four channels to be loaded with the same coefficients with a single data
transfer from the master controller. This allows for a faster initialization of the device after a powerup. This com-
mand should be used with caution since it affects all four channels. The normal memory write and read commands
affect only one channel.
Reset Functionality
The reset function allows the internal logic of the device to be set to a known initial condition, either externally by
activating the reset lead, or on a per-channel basis through the microprocessor interface by setting and then clear-
ing bits, if required, in address RESCTRL (address 128). These two reset functions have different effects, and
each of the software reset functions is a subset of the hardware reset functionality. The primary difference is in the
treatment of the internal memory. The hardware reset is assumed to be a result of a catastrophic hardware event,
such as a loss of power, loss of BCLK, or an initial powerup. Accordingly, the assumption is made that the internal
memory does not contain valid data, and default values for all memory locations are loaded. A software reset, how-
ever, can only be initiated if the device is operational (at least the microprocessor interface), so the contents of the
memory may indeed be valid; thus, the resets may be more specific. Additionally, software resets only affect the
selected channel.
BCLK
RST
FS
(continued)
RUNS CONTINUOUSLY
RUNS CONTINUOUSLY
1 ms
(continued)
Figure 20. Hardware Reset Procedure
DEVICE CAN NOW BE PROGRAMMED
T8535B/T8536B Quad Programmable Codec
WAIT
5 ms
0071c
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