Definition For Start And End Of Frame Symbols; Huntzicker Symbol Timing Characteristics - Intel 87C196CA Supplement To User’s Manual

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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
Logic Level 0
Logic Level 1
Start of Frame
End of Data
End of Frame
In-frame Separation
Break
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.
200µS
"Start of Frame (SOF)"
200µS
"End of Data (EOD)"
280µS
"End of Frame (EOF)"
300µS+
"In-frame Separation (IFS)"
768µS+
"Break Signal (BRK)"
Bus Level T
TX
Passive 60
0
Active 122
Passive 122
1
Active 60
SOF Active 193
EOD Passive 193
EOF Passive 271
IFS Passive >300
BRK Active 768
J1850 COMMUNICATIONS CONTROLLER
min T nom T max
TX TX
64 68
128 134
128 134
64 68
200 207
200 207
280 289
— —
— —
A5221-01
T min T max Units
RX RX
34 <96 µs
96 <163 µs
96 <163 µs
34 <96 µs
163 <239 µs
163 <239 µs
239 <300 µs
>300 — µs
>239 — µs
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