MC68HC55 Datasheet, PDF (5/40 Pages) Freescale Semiconductor, Inc – Two-Channel CMOS ASIC Device

MC68HC55 Technical Data
Pin Assignments
The second message assigns the address to the second node and
receives a response message from the first node at the same time. The
first node ignores the second address assignment message because it
already has an address. During the third address assignment message,
only the second node responds (a node only responds to the assignment
message once).This sequence continues until all nodes have been
assigned addresses and have responded that the assignment was
successful.
Now that the nodes each have a unique address, messages can be sent
and received from individual nodes. Notice that during a message, the
node that is receiving the command and the node that is returning a
response are not necessarily the same node.
Nodes do not have any permanently programmed address. Addresses
are assigned according to the order of the devices on the bus every time
power is applied. Multiple nodes may be replaced and/or the system can
be reconfigured by adding nodes to the bus, and the system will
automatically reconfigure itself at the next power-on.
Section 2. MC68HC55CD Pin Assignments and Descriptions
Refer to Figure 2-1 for the MC68HC55CD pin assignments. A brief
description of the pins is given in this section.
2.1 Pin Assignments
SCLK
1
CLK
2
DI
3
DO
4
CS
5
RESET
6
INT
7
GND
8
16
V_DD
15
DSI0F
14
DSI0S
13
DSI0R
12
N/C
11
DSI1F
10
DSI1S
9
DSI1R
16-lead narrow body SOIC, package #751B-05 issue J
Figure 2-1. MC68HC55CD Pin Assignments
MC68HC55
MC68HC55CD Pin Assignments and Descriptions
Technical Data
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