Datasheet

MPC8309 PowerQUICC II Pro Integrated Communications Processor Family Hardware Specifications, Rev. 2
36 Freescale Semiconductor
DUART
13 DUART
This section describes the DC and AC electrical specifications for the DUART interface of the MPC8309.
13.1 DUART DC electrical characteristics
The following table provides the DC electrical characteristics for the DUART interface of the MPC8309.
13.2 DUART AC electrical specifications
The following table provides the AC timing parameters for the DUART interface of the MPC8309.
Table 35. DUART DC electrical characteristics
Parameter Symbol Min Max Unit
High-level input voltage V
IH
2OV
DD
+0.3 V
Low-level input voltage OV
DD
V
IL
–0.3 0.8 V
High-level output voltage, I
OH
= –100 μAV
OH
OV
DD
–0.2 — V
Low-level output voltage, I
OL
= 100 μAV
OL
—0.2V
Input current (0 V ≤ V
IN
≤ OV
DD
)
1
I
IN
—±5μA
Note:
1. Note that the symbol V
IN
, in this case, represents the OV
IN
symbol referenced in Ta bl e 1 and Tab le 2 .
Table 36. DUART AC timing specifications
Parameter Value Unit Note
Minimum baud rate 256 baud —
Maximum baud rate >1,000,000 baud 1
Oversample rate 16 — 2
Notes:
1. Actual attainable baud rate is limited by the latency of interrupt processing.
2. 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.