DUART
7
DUART
This section describes the DC and AC electrical specifications for the DUART interface of the
MPC8548E.
7.1
DUART DC Electrical Characteristics
Table 20. DUART DC Electrical Characteristics
Parameter
Symbol
V
IH
V
IL
I
IN
V
OH
V
OL
Min
2
–0.3
—
2.4
—
Max
OV
DD
+ 0.3
0.8
±5
—
0.4
Unit
V
V
μA
V
V
provides the DC electrical characteristics for the DUART interface.
High-level input voltage
Low-level input voltage
Input current (V
IN1
= 0 V or V
IN
= V
DD)
High-level output voltage (OV
DD
= min, I
OH
= –2 mA)
Low-level output voltage (OV
DD
= min, I
OL
= 2 mA)
Note:
1. Note that the symbol V
IN
, in this case, represents the OV
IN
symbol referenced in
and
7.2
DUART AC Electrical Specifications
Table 21. DUART AC Timing Specifications
Parameter
Value
f
CCB
/1,048,576
f
CCB
/16
16
Unit
baud
baud
—
Notes
1, 2
1, 2, 3
1, 4
provides the AC timing parameters for the DUART interface.
Minimum baud rate
Maximum baud rate
Oversample rate
Notes:
1. Guaranteed by design.
2. f
CCB
refers to the internal platform clock.
3. Actual attainable baud rate will be limited by the latency of interrupt processing.
4. The middle of a start bit is detected as the 8
th
sampled 0 after the 1-to-0 transition of the start bit. Subsequent bit values are
sampled each 16
th
sample.
MPC8548E PowerQUICC™ III Integrated Processor Hardware Specifications, Rev. 6
Freescale Semiconductor
25
FREESCALE [ FREESCALE SEMICONDUCTOR, INC ]
