Intel 8XC196Lx Manuale Utente
8-11
J1850 COMMUNICATIONS CONTROLLER
Figure 8-8. Definition for Start and End of Frame Symbols
Table 8-4 details the symbol timing characteristics supported by the 87C196LB.
Table 8-4. Huntzicker Symbol Timing Characteristics
Name
Symbol
Bus Level
T
TX
min
T
TX
nom
T
TX
max
T
RX
min
T
RX
max
Units
Logic Level 0
0
Passive
60
64
68
34
<96
µs
Active
122
128
134
96
<163
µs
Logic Level 1
1
Passive
122
128
134
96
<163
µs
Active
60
64
68
34
<96
µs
Start of Frame
SOF
Active
193
200
207
163
<239
µs
End of Data
EOD
Passive
193
200
207
163
<239
µs
End of Frame
EOF
Passive
271
280
289
239
<300
µs
In-frame Separation
IFS
Passive
>300
—
—
>300
—
µs
Break
BRK
Active
768
—
—
>239
—
µs
NOTE:
Timings are based on the standard bus rate of 10.4 Kb/s. When operating in 4x mode, the bus
rate becomes 41.6 Kb/s and all symbol timings are one fourth that shown.
rate becomes 41.6 Kb/s and all symbol timings are one fourth that shown.
A5221-01
0
1
0
1
"Break Signal (BRK)"
"In-frame Separation (IFS)"
300µS+
0
1
200µS
0
1
"End of Frame (EOF)"
280µS
0
1
768µS+
200µS
"Start of Frame (SOF)"
"End of Data (EOD)"