MCHC908JW32FAE Freescale Semiconductor, MCHC908JW32FAE Datasheet - Page 193
![IC MCU 32K FLASH 8MHZ 48-LQFP](/photos/12/35/123518/mchc908jw32fae_sml.jpg)
MCHC908JW32FAE
Manufacturer Part Number
MCHC908JW32FAE
Description
IC MCU 32K FLASH 8MHZ 48-LQFP
Manufacturer
Freescale Semiconductor
Series
HC08r
Datasheet
1.RD3152MMA7260Q.pdf
(232 pages)
Specifications of MCHC908JW32FAE
Core Processor
HC08
Core Size
8-Bit
Speed
8MHz
Connectivity
SPI, USB
Peripherals
LED, LVD, POR, PWM
Number Of I /o
29
Program Memory Size
32KB (32K x 8)
Program Memory Type
FLASH
Ram Size
1K x 8
Voltage - Supply (vcc/vdd)
3.5 V ~ 5.5 V
Oscillator Type
Internal
Operating Temperature
0°C ~ 70°C
Package / Case
48-LQFP
Controller Family/series
HC08
No. Of I/o's
48
Ram Memory Size
1KB
Cpu Speed
8MHz
No. Of Timers
1
Embedded Interface Type
SPI
Rohs Compliant
Yes
Processor Series
HC08JW
Core
HC08
Data Bus Width
8 bit
Data Ram Size
1 KB
Interface Type
SPI, USB
Number Of Programmable I/os
29
Number Of Timers
2
Maximum Operating Temperature
+ 70 C
Mounting Style
SMD/SMT
Development Tools By Supplier
FSICEBASE, DEMO908GZ60E, M68EML08GZE, KITUSBSPIDGLEVME, KITUSBSPIEVME, KIT33810EKEVME
Minimum Operating Temperature
0 C
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Eeprom Size
-
Data Converters
-
Lead Free Status / Rohs Status
Details
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
MCHC908JW32FAE
Manufacturer:
Freescale Semiconductor
Quantity:
10 000
Part Number:
MCHC908JW32FAE
Manufacturer:
FREESCALE
Quantity:
20 000
The vector fetch or software clear and the return of all enabled keyboard interrupt pins to logic 1 may
occur in any order.
If the MODEK bit is clear, the keyboard interrupt pin is falling-edge-sensitive only. With MODEK clear, a
vector fetch or software clear immediately clears the keyboard interrupt request.
Reset clears the keyboard interrupt request and the MODEK bit, clearing the interrupt request even if a
keyboard interrupt pin stays at logic 0.
The keyboard flag bit (KEYF) in the keyboard status and control register can be used to see if a pending
interrupt exists. The KEYF bit is not affected by the keyboard interrupt mask bit (IMASKK) which makes
it useful in applications where polling is preferred.
To determine the logic level on a keyboard interrupt pin, use the data direction register to configure the
pin as an input and read the data register.
15.4.1 Keyboard Initialization
When a keyboard interrupt pin is enabled, it takes time for the pullup device to reach a logic 1. Therefore,
a false interrupt can occur as soon as the pin is enabled.
To prevent a false interrupt on keyboard initialization:
An interrupt signal on an edge-triggered pin can be acknowledged immediately after enabling the pin. An
interrupt signal on an edge- and level-triggered interrupt pin must be acknowledged after a delay that
depends on the external load.
Another way to avoid a false interrupt:
Freescale Semiconductor
1. Mask keyboard interrupts by setting the IMASKK bit in the keyboard status and control register.
2. Enable the KBI pins by setting the appropriate KBIEx bits in the keyboard interrupt enable register.
3. Write to the ACKK bit in the keyboard status and control register to clear any false interrupts.
4. Clear the IMASKK bit.
1. Configure the keyboard pins as outputs by setting the appropriate DDRA bits in data direction
2. Write logic 1s to the appropriate port A data register bits.
3. Enable the KBI pins by setting the appropriate KBIEx bits in the keyboard interrupt enable register.
register A.
Setting a keyboard interrupt enable bit (KBIEx) forces the corresponding
keyboard interrupt pin to be an input, overriding the data direction register.
However, the data direction register bit must be a logic 0 for software to
read the pin.
MC68HC908JW32 Data Sheet, Rev. 6
NOTE
Functional Description
193