mc68332acpv25b1 Freescale Semiconductor, Inc, mc68332acpv25b1 Datasheet - Page 36

• Manufacturer Part Number: mc68332acpv25b1
• Description: Technical Summary 32-bit Modular Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

AVEC — Autovector Enable
3.5.5 Port C Data Register
PORTC — Port C Data Register
3.6 General-Purpose Input/Output
PORTE0, PORTE1 —Port E Data Register
DDRE — Port E Data Direction Register
36
MOTOROLA
RESET:
RESET:
RESET:
15
15
15
This field selects one of two methods of acquiring the interrupt vector during the interrupt acknowledge
cycle. It is not usually used in conjunction with a chip-select pin.
If the chip select is configured to trigger on an interrupt acknowledge cycle (SPACE = 00) and the AVEC
field is set to one, the chip select automatically generates an AVEC in response to the interrupt cycle.
Otherwise, the vector must be supplied by the requesting device.
The AVEC bit must not be used in synchronous mode, as autovector response timing can vary because
of ECLK synchronization.
Bit values in port C determine the state of chip-select pins used for discrete output. When a pin is as-
signed as a discrete output, the value in this register appears at the output. This is a read/write register.
Bit 7 is not used. Writing to this bit has no effect, and it always returns zero when read.
SIM pins can be configured as two general-purpose I/O ports, E and F. The following paragraphs de-
scribe registers that control the ports.
A write to the port E data register is stored in the internal data latch and, if any port E pin is configured
as an output, the value stored for that bit is driven on the pin. A read of the port E data register returns
the value at the pin only if the pin is configured as a discrete input. Otherwise, the value read is the value
stored in the register.
The port E data register is a single register that can be accessed in two locations. When accessed at
$YFFA11, the register is referred to as PORTE0; when accessed at $YFFA13, the register is referred
to as PORTE1. The register can be read or written at any time. It is unaffected by reset.
The bits in this register control the direction of the pin drivers when the pins are configured as I/O. Any
bit in this register set to one configures the corresponding pin as an output. Any bit in this register
cleared to zero configures the corresponding pin as an input. This register can be read or written at any
time.
0 = External interrupt vector enabled
1 = Autovector enabled
NOT USED
NOT USED
NOT USED
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
8
8
8
DDE7
PE7
7
0
0
7
U
7
0
DDE6
PC6
PE6
U
6
1
6
6
0
DDE5
PC5
PE5
U
5
1
5
5
0
DDE4
PC4
PE4
U
4
1
4
4
0
DDE3
PC3
PE3
U
3
1
3
3
0
$YFFA11, $YFFA13
DDE2
PC2
PE2
U
2
1
2
2
0
MC68332TS/D
DDE1
PC1
PE1
U
$YFFA41
1
1
1
$YFFA15
1
0
MC68332
DDE0
PC0
PE0
0
1
0
U
0
0