MC68HC908GT16 Datasheet, PDF (294/412 Pages) Motorola, Inc – Microcontrollers

Enhanced Serial Communications Interface (ESCI)
18.10.4 Arbitration Mode
If AM[1:0] is set to 10, the arbiter module operates in arbitration mode.
On every rising edge of SCI_TxD (output of the ESCI module, internal
chip signal), the counter is started. When the counter reaches $38
(ACLK = 0) or $08 (ACLK = 1), RxD is statically sensed. If in this case,
RxD is sensed low (for example, another bus is driving the bus
dominant) ALOST is set. As long as ALOST is set, the TxD pin is forced
to 1, resulting in a seized transmission.
If SCI_TxD is sensed logic 0 without having sensed a logic 0 before on
RxD, the counter will be reset, arbitration operation will be restarted after
the next rising edge of SCI_TxD.
Technical Data
294
MC68HC908GT16 • MC68HC908GT8 — Rev. 2
Enhanced Serial Communications Interface (ESCI) Module
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