Reduced Instruction Set Computer (Risc) - Tait TB8100 Service Manual

CODECs
2.1.3

Reduced Instruction Set Computer (RISC)

Hardware and I/O
32 Reciter Circuit Description
The three CODECs provide the audio frequency analogue interface to the
reciter. There are six analogue input and six analogue output paths. The
sample rate on all paths is 25kSPS and the sampling resolution is 16 bits.
The CODEC inputs are as follows:
two input signals from the frequency control loop (FCL)
balanced line input
unbalanced line input
microphone input
synthesizer loop control voltage.
The CODEC outputs are as follows:
VCO voltage control line
VCXO voltage control line
balanced line output
unbalanced line output
speaker output
RSSI voltage indicator.
Refer to Figure 2.3 on page
The RISC processor engine is a Samsung S3C3410X processor with a
40MHz external clock. It has 4 megabytes of flash memory containing the
following:
bootloader
application code
DSP code
non-volatile data
2 megabytes of RAM for run-time variables.
The discrete digital inputs and outputs are as follows:
chip select signals to synthesizers
out-of-lock signals from synthesizers
external reference detection
internal/external reference selection
Rx Gate output
Tx Relay output
reciter hex switch
reciter alarm LED
DIP switch for manufacturing testing
33.
© Tait Electronics Limited September 2006
TB8100 Service Manual