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ELS31-VA/ELS51-VA Hardware Interface Description
2.1 Application Interface
56
ELS31-VA_ELS51-VA_HID_v01.000
2017-01-04
Confidential / Preliminary
Page 44 of 106
shows the described RING0 wake up mechanism:
•
RING0 shall be high
•
After a given programmable timeout with no activity on ASC0, RTS0 will be driven high and
the host will fall asleep if RING0 remains high (note: Host shall wait at least for one UART
character after RTS0 is driven high before entering sleep mode, to catch the last potential
character transmission over UART)
•
The module will wake-up the host driving RING0 from high to low
•
The Host will inform the module it is ready to receive over UART by driving RTS0 to low
Figure 20:
Wake-up via RING0
R IN G 0
H o st w a ke -u p e ve n t b y
m o d u le
H o st is re a d y to re ce ive
o ve r U A R T
R T S 0
H o st e n te rs sle e p m o d e