TMC2072_07 SMSC [SMSC Corporation], TMC2072_07 Datasheet - Page 48

• Manufacturer Part Number: TMC2072_07
• Manufacturer: SMSC [SMSC Corporation]

2.11.1 Functions Provided by NST
Revision 0.1 (06-07-07)
N S T P re sca le
N S T P re sca le
N S T P R E [2 :0 ]
N S T P R E [2 :0 ]
The NST prescaler pin (NSTPRE2, 0) is used to set the count speed of the NST. The following table lists
the relations among setting, resolution, and maximum time:
Automatic generation of packet with time stamp
Setting one (1) to the NSTSEND bit in the MODE register allows the last 2 bytes in a packet to be reserved
for the NST area, and the newest value of NST is automatically sent in these 2 bytes (nothing is written in
the sending buffer RAM).
In the case of the clock master node (described in a later section), the same operation is carried out
regardless of the NSTSEND value. The value is used as the time stamp of the packet and also used to
maintain synchronization of time on the network.
NST carry output
The change of any digit in NST can be output as a periodic pulse to the nNSTCOUT pin. NSTC [3:0] in the
CARRY register (external pin in the standalone mode) is used to select the digit. The pulse width of the
carry output is the same length as one cycle of the NST resolution. As long as NST is synchronized
properly, every node can output the pulse with the same phase.
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
000
001
010
011
100
101
110
111
P re s ca le
P re sca le
1 :1 0 2 4
1 :2 0 4 8
1 :4 0 9 6
1 :1 0 2 4
1 :2 0 4 8
1 :4 0 9 6
1 :1 2 8
1 :2 5 6
1 :5 1 2
1 :1 2 8
1 :2 5 6
1 :5 1 2
1 :3 2
1 :6 4
1 :3 2
1 :6 4
R e so lu tio n
R e so lu tio n
DATASHEET
1 2 8 .0 u s
1 0 2 .4 u s
1 6 .0 u s
3 2 .0 u s
6 4 .0 u s
1 2 .8 u s
2 5 .6 u s
5 1 .2 u s
1 .0 u s
2 .0 u s
4 .0 u s
8 .0 u s
0 .8 u s
1 .6 u s
3 .2 u s
6 .4 u s
3 2 M H z X ta l
4 0 M H z X ta l
Page 48
M A X P e rio d
M A X P e rio d
5 2 .4 m s
1 0 5 m s
2 1 0 m s
4 1 9 m s
8 3 9 m s
0 .0 7 s
0 .1 3 s
0 .2 6 s
0 .5 2 s
1 .0 5 s
2 .1 0 s
4 .1 9 s
8 .3 9 s
1 .6 8 s
3 .3 6 s
6 .7 1 s
R e s o lu tio n
R e so lu tio n
1 0 2 .4 u s
2 0 4 .8 u s
1 2 8 .0 u s
2 5 6 .0 u s
Peripheral Mode CircLink™ Controller
1 2 .8 u s
2 5 .6 u s
5 1 .2 u s
1 6 .0 u s
3 2 .0 u s
6 4 .0 u s
1 .6 u s
3 .2 u s
6 .4 u s
2 .0 u s
4 .0 u s
8 .0 u s
1 6 M H z X ta l
2 0 M H z X ta l
M A X P e rio d
M A X P e rio d
SMSC TMC2072
1 6 .7 8 s
1 0 5 m s
2 1 0 m s
4 1 9 m s
8 3 9 m s
1 3 .4 2 s
Datasheet
1 .6 8 s
3 .3 6 s
6 .7 1 s
0 .1 3 s
0 .2 6 s
0 .5 2 s
1 .0 5 s
2 .1 0 s
4 .1 9 s
8 .3 9 s