Motorola MC68HC908AB32 User Manual

Serial Communications Interface
Technical Data MC68HC908AB32 — Rev. 1.0
256 Serial Communications Interface Module (SCI) MOTOROLA
With the misaligned character shown in Figure 15-7, the receiver counts
170 RT cycles at the point when the count of the transmitting device is
10 bit times × 16 RT cycles + 3 RT cycles = 163 RT cycles.
The maximum percent difference between the receiver count and the
transmitter count of a slow 9-bit character with no errors is
Fast Data Tolerance
Figure 15-8 shows how much a fast received character can be
misaligned without causing a noise error or a framing error. The fast stop
bit ends at RT10 instead of RT16 but is still there for the stop bit data
samples at RT8, RT9, and RT10.
Figure 15-8. Fast Data
For an 8-bit character, data sampling of the stop bit takes the receiver
9 bit times × 16 RT cycles + 10 RT cycles = 154 RT cycles.
With the misaligned character shown in Figure 15-8, the receiver counts
154 RT cycles at the point when the count of the transmitting device is
10 bit times × 16 RT cycles = 160 RT cycles.
The maximum percent difference between the receiver count and the
transmitter count of a fast 8-bit character with no errors is
170 163–
170
--------------------------
100× 4.12%=
IDLE OR NEXT CHARACTERSTOP
RT1 RT2 RT3 RT4 RT5 RT6 RT7 RT8 RT9
RT10 RT11 RT12 RT13 RT14 RT15 RT16
DATA
SAMPLES
RECEIVER
RT CLOCK
154 160–
154
--------------------------
100× 3.90%
˙
=

Motorola MC68HC908AB32 Specifications

General

Brand	Motorola
Model	MC68HC908AB32
Category	Controller
Language	English