RS8973 Mindspeed Technologies, RS8973 Datasheet - Page 61

• Manufacturer Part Number: RS8973
• Description: Single-chip Sdsl/hdsl Transceiver
• Manufacturer: Mindspeed Technologies

RS8973
Single-Chip SDSL/HDSL Transceiver
Independent read/write restart bits, one for each of the eight internal timers. Setting an individual bit causes the
associated timer to be reloaded with the contents of its interval register. For the four symbol-rate timers (meter,
snr, t3, t4), reloading occurs within 1 symbol period. For the four start-up timers (sut1–4), reloading occurs
within 1024 symbol periods. Once the timer is reloaded, the restart bit is automatically cleared. If a restart bit is
set and then cleared (by writing a logical 0) before the reload actually takes place, no timer reload occurs. Once
reloaded, if enabled in the Timer Enable Register [timer_enable; 0x0D], the timer begins counting down toward
zero; otherwise, it holds at the interval register value.
t4
t3
snr
meter
sut4
sut3
sut2
sut1
Independent read/write enable bits, one for each of the eight internal timers. When any individual bit is set, the
corresponding timer is enabled for counting down from its current value toward 0. For the four symbol-rate
timers (meter, snr, t3, t4), counting begins within 1 symbol period. For the four start-up timers (sut1-4), counting
begins within 1024 symbol periods. When an enable bit is cleared, the timer is disabled from counting and holds
its current value. If an enable bit is set and then cleared before a count actually takes place, no timer countdown
occurs.
t4
t3
snr
meter
sut4
sut3
sut2
sut1
N8973DSD
0x0C—Timer Restart Register (timer_restart)
0x0D—Timer Enable Register (timer_enable)
t4
t4
7
7
General Purpose Timer 4
General Purpose Timer 3
SNR Alarm Timer
Meter Timer
Startup Timer 4
Startup Timer 3
Startup Timer 2
Startup Timer 1
General Purpose Timer 4
General Purpose Timer 3
SNR Alarm Timer
Meter Timer
Startup Timer 4
Startup Timer 3
Startup Timer 2
Startup Timer 1
t3
t3
6
6
snr
snr
5
5
Preliminary Information
meter
meter
4
4
Conexant
sut4
sut4
3
3
sut3
sut3
2
2
sut2
sut2
3.3 Register Description
1
1
3.0 Registers
sut1
sut1
0
0
3-15