MOTOROLA
SYSTEM INTEGRATION MODULE
M68HC16 Z SERIES
5-54
USER’S MANUAL
NOTE
Pins that are not used should either be configured as outputs, or (if
configured as inputs) pulled to the appropriate inactive state. This de-
creases additional IDD caused by digital inputs floating near mid-sup-
ply level.
5.7.5.1 Reset States of SIM Pins
Generally, while RESET is asserted, SIM pins either go to an inactive high-impedance
state or are driven to their inactive states. After RESET is released, mode selection
occurs, and reset exception processing begins. Pins configured as inputs must be
driven to the desired active state. Pull-up or pull-down circuitry may be necessary. Pins
configured as outputs begin to function after RESET is released. Table 5-21 is a sum-
mary of SIM pin states during reset.
5.7.5.2 Reset States of Pins Assigned to Other MCU Modules
As a rule, module pins that are assigned to general-purpose I/O ports go into a high-
impedance state following reset. However, during power-on reset, module port pins
for more information.
Table 5-21 SIM Pin Reset States
Pin(s)
Pin State
While RESET
Asserted
Pin State After RESET Released
Default Function
Alternate Function
Pin Function
Pin State
Pin Function
Pin State
CS10/ADDR23/ECLK
VDD
CS10
VDD
ADDR23
Unknown
CS[9:6]/ADDR[22:19]/PC[6:3]
VDD
CS[9:6]
VDD
ADDR[22:19]
Unknown
ADDR[18:0]
High-Z
ADDR[18:0]
Unknown
ADDR[18:0]
Unknown
AS/PE5
High-Z
AS
Output
PE5
Input
AVEC/PE2
High-Z
AVEC
Input
PE2
Input
BERR
High-Z
BERR
Input
BERR
Input
CS1/BG
VDD
CS1
VDD
BG
VDD
CS2/BGACK
VDD
CS2
VDD
BGACK
Input
CS0/BR
VDD
CS0
VDD
BR
Input
CLKOUT
Output
CLKOUT
Output
CLKOUT
Output
CSBOOT
VDD
CSBOOT
VSS
CSBOOT
VSS
DATA[15:0]
Mode select
DATA[15:0]
Input
DATA[15:0]
Input
DS/PE4
High-Z
DS
Output
PE4
Input
DSACK0/PE0
High-Z
DSACK0
Input
PE0
Input
DSACK1/PE1
High-Z
DSACK1
Input
PE1
Input
CS[5:3]/FC[2:0]/PC[2:0]
VDD
CS[5:3]
VDD
FC[2:0]
Unknown
HALT
High-Z
HALT
Input
HALT
Input
IRQ[7:1]/PF[7:1]
High-Z
IRQ[7:1]
Input
PF[7:1]
Input
MODCLK/PF0
Mode Select
MODCLK
Input
PF0
Input
R/W
High-Z
R/W
Output
R/W
Output
RESET
Asserted
RESET
Input
RESET
Input
SIZ[1:0]/PE[7:6]
High-Z
SIZ[1:0]
Unknown
PE[7:6]
Input
TSC
Mode select
TSC
Input
TSC
Input