AMIS-49587 Datasheet, PDF (19/59 Pages) ON Semiconductor – Power Line Carrier Modem

T_REQ
AMIS−49587
t_POLL
TxD
Status ?
tSR
ACK
t ACK
RxD
Local Frame from Base Micro
Figure 15. Transfer from Base Micro to AMIS−49587
If the length and the checksum of the local frame are both
correct, the AMIS−49587 acknowledges with an <ACK>
character. In other cases, it answers with a <NAK>
character. In case of <NAK> response, or no
acknowledgement from AMIS−49587 in the Tack time−out,
a complete sequence must be restarted to repeat the frame.
Transfer from AMIS−49587 to Base Micro
When the AMIS−49587 wants to send a frame, it can
directly send it without any previous request.
T_REQ
TxD
Local Frame from
AMIS −49587
Local Frame from
AMIS−49587
Local Frame from
AMIS−49587
t_ACK
t_WBC
t_ACK
t_WBC
RxD
NAK
ACK
Figure 16. Transfer from AMIS−49587 to Base Micro
If the length and the checksum of the local frame are both
correct, the base micro acknowledges with an <ACK>
character. In other cases, it answers with a <NAK>
character. In case of <NAK> response from the Base Micro,
the AMIS−49587 will repeat the frame only once after a
delay corresponding to Twbc (Wait Before Continue). A non
response from the base micro or a framing error when an
<ACK> character is awaited is considered as an
acknowledgment.
Character Time−out in Reception
The time between two consecutive characters in a local
frame should not exceed Time−out Inter Character (TIC):
t_IC
Character
Character
t
Figure 17. Character Time−Out
After this delay, the frame reception is finished. If the
length and the checksum are both correct, the local frame is
taken in account otherwise all previous characters are
discarded. The Time−Out Inter Character (TIC) is set by
default at 10 ms after a reset. The time out Inter character
http://onsemi.com
19