s908ey16g2vfar Freescale Semiconductor, Inc, s908ey16g2vfar Datasheet - Page 161

• Manufacturer Part Number: s908ey16g2vfar
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

13.9.3 Bit Time Measurement
Two bit time measurement modes, described here, are available according to the state of ACLK.
Freescale Semiconductor
1. ACLK = 0 — The counter is clocked with one quarter of the ESCI input clock (= bus or CGMXCLK,
2. ACLK = 1 — The counter is clocked with one quarter of the ESCI input clock divided by the ESCI
see
counter is started when a falling edge on the RxD pin is detected. The counter will be stopped on
the next falling edge. ARUN is set while the counter is running, AFIN is set on the second falling
edge on RxD (for instance, the counter is stopped). This mode is used to recover the received baud
rate. See
prescaler. The counter is started when a logic 0 is detected on RxD (see
on RxD on enabling the bit time measurement with ACLK = 1 leads to immediate start of the
counter (see
is used to measure the length of a received break.
Figure 5-2. Configuration Register 2 (CONFIG2)
RXD
RXD
Figure
Figure 13-22. Bit Time Measurement with ACLK = 1, Scenario A
Figure
13-21.
Figure 13-21. Bit Time Measurement with ACLK = 0
13-23). The counter will be stopped on the next rising edge of RxD. This mode
MC68HC908EY16A • MC68HC908EY8A Data Sheet, Rev. 1
MEASURED TIME
MEASURED TIME
for a description of the ESCIBDSRC bit). The
Figure
13-22). A logic 0
ESCI Arbiter
161