s908qy2ad1vdwer Freescale Semiconductor, Inc, s908qy2ad1vdwer Datasheet - Page 195

• Manufacturer Part Number: s908qy2ad1vdwer
• Description: Mc68hc908qt4a Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

A.2.5 Keyboard Interface Module (KBI) Functionality
The KBI module for the QYxA has the added capability of:
A.2.5.1 Registers Affected
The KBIPR allows the selection of polarity, if any of these bits are set the corresponding interrupt pin will
be configured for rising edge and a pulldown resistor will be added to the pin.
A.2.6 On-Chip Routine Enhancements
Enhancements have been made to the on-chip routines that are used for FLASH as EEPROM. Refer to
AN2346 for information about using FLASH as EEPROM.
Freescale Semiconductor
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Triggering a KBI interrupt on the rising or falling edge of an input while the QYx Classic has the
capability of triggering on falling edges only.
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A new mass erase routine requires a valid FLASH address loaded into the H:X register to perform
an erase. This added step helps ensure that the erase routine is not inadvertently used to cause
an unwanted erase. Also, on-chip FLASH programming routine ERARNGE variable CTRLBYT
requires $00 for page erase and $40 for mass erase. The entire control byte must be set for proper
operation.
Separate routines will allow easy access to perform software SCI (Serial Communications
Interface). For information on how to use on-chip FLASH programming routines refer to AN2635.
Finally, there is improved security and robustness. The latest Monitor ROM implements updated
security checks to make the program memory more secure.
A new register (Keyboard Interrupt Polarity Register) determines the polarity of KBI and the
default state of this register configures the QYxA for triggering on falling edges to be compatible
with QYx Classic.
The QYxA now has pull down resistors for the input pins that are configured for rising edge
operation.
Reset:
Read:
Write:
Figure A-6. Keyboard Interrupt Polarity Register (KBIPR)
Bit 7
0
0
= Unimplemented
MC68HC908QYA/QTA Family Data Sheet, Rev. 2
0
6
0
KBIP5
5
0
KBIP4
4
0
KBIP3
3
0
KBIP2
2
0
KBIP1
1
0
KBIP0
Bit 0
0
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