REGISTER SUMMARY
M68HC16 Z SERIES
D-16
USER’S MANUAL
This register contains seven 2-bit fields that determine the function of corresponding
chip-select pins. Bits [15:14] are not used. These bits always read zero; writes have
no effect. CSPAR0 bit 1 always reads one; writes to CSPAR0 bit 1 have no effect. The
alternate functions can be enabled by data bus mode selection during reset. This reg-
ister may be read or written at any time. After reset, software may enable one or more
pins as discrete outputs.
CSPAR1 contains five 2-bit fields that determine the functions of corresponding chip-
select pins. Bits [15:10] are not used. These bits always read zero; writes have no ef-
fect.
shows CSPAR1 pin assignments, including alternate functions that
can be enabled by data bus mode selection during reset.
Table D-8 Pin Assignment Field Encoding
CSxPA[1:0]
Description
00
Discrete output
1
NOTES:
1. Does not apply to the CSBOOT field.
01
Alternate function
10
Chip-select (8-bit port)
11
Chip-select (16-bit port)
Table D-9 CSPAR0 Pin Assignments
CSPAR0 Field
Chip-Select Signal
Alternate Signal
Discrete Output
CS5PA[1:0]
CS5
FC2
PC2
CS4PA[1:0]
CS4
FC1
PC1
CS3PA[1:0]
CS3
FC0
PC0
CS2PA[1:0]
CS2
BGACK
—
CS1PA[1:0]
CS1
BG
—
CS0PA[1:0]
CS0
BR
—
CSBTPA[1:0]
CSBOOT
—
—
CSPAR1 — Chip-Select Pin Assignment Register 1
$YFFA46
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
0
0
0
0
0
CS10PA[1:0]
CS9PA[1:0]
CS8PA[1:0]
CS7PA[1:0]
CS6PA[1:0]
RESET:
0
0
0
0
0
0
DATA7
1
NOTES:
1. Refer to
for CSPAR1 reset state information.
1
DATA
[7:6]
1
DATA
[7:5]
1
DATA
[7:4]
1
DATA
1
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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