7.4 Input glitch filter setting
A filter is implemented for each port pin that is configured as a digital input. It can be
used as a simple low-pass filter to filter any glitch that is introduced from the pins of
GPIO, IRQ,RESET, and KBI. The glitch width threshold can be adjusted easily by
setting registers PORT_IOFLTn and PORT_FCLKDIV between 1~4096 BUSCLKs (or
1~128 LPOCLKs). This configurable glitch filter can take the place of an on board
external analog filter, and greatly improve the EMC performance.
Setting register PORT_IOFLTn can configure the filter of the whole port, etc. set
PORT_IOFLT0[FLTA] will affect all PTAn pins.
7.5 High current drive
Output high sink/source current drive can be enabled by setting the corresponding bit in
the HDRVE register for PTB5 and PTB4. Output high sink/source current when they are
operated as output. High current drive function is disabled if the pin is configured as an
input by the parallel I/O control logic. When configured as any shared peripheral
function, high current drive function still works on these pins, but only when they are
configured as outputs.
7.6 Pin behavior in stop mode
In stop3 mode, all I/O is maintained because internal logic circuitry stays powered up.
Upon recovery, normal I/O function is available to the user.
7.7 Port data registers
PORT memory map
Absolute
address
(hex)
Register name
Width
(in bits)
Access Reset value
Section/
page
0
Port A Data Register (PORT_PTAD)
8
R/W
00h
1
Port B Data Register (PORT_PTBD)
8
R/W
00h
2
Port C Data Register (PORT_PTCD)
8
R/W
00h
30AF
Port High Drive Enable Register (PORT_HDRVE)
8
R/W
00h
Table continues on the next page...
Input glitch filter setting
MC9S08PA4 Reference Manual, Rev. 5, 08/2017
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NXP Semiconductors
Summary of Contents for MC9S08PA4
Page 1: ...MC9S08PA4 Reference Manual Supports MC9S08PA4 Document Number MC9S08PA4RM Rev 5 08 2017 ...
Page 2: ...MC9S08PA4 Reference Manual Rev 5 08 2017 2 NXP Semiconductors ...
Page 22: ...MC9S08PA4 Reference Manual Rev 5 08 2017 22 NXP Semiconductors ...
Page 28: ...System clock distribution MC9S08PA4 Reference Manual Rev 5 08 2017 28 NXP Semiconductors ...
Page 150: ...Port data registers MC9S08PA4 Reference Manual Rev 5 08 2017 150 NXP Semiconductors ...
Page 196: ...Human machine interfaces HMI MC9S08PA4 Reference Manual Rev 5 08 2017 196 NXP Semiconductors ...
Page 224: ...Instruction Set Summary MC9S08PA4 Reference Manual Rev 5 08 2017 224 NXP Semiconductors ...
Page 232: ...Functional Description MC9S08PA4 Reference Manual Rev 5 08 2017 232 NXP Semiconductors ...
Page 258: ...FTM Interrupts MC9S08PA4 Reference Manual Rev 5 08 2017 258 NXP Semiconductors ...
Page 294: ...Functional description MC9S08PA4 Reference Manual Rev 5 08 2017 294 NXP Semiconductors ...
Page 398: ...Resets MC9S08PA4 Reference Manual Rev 5 08 2017 398 NXP Semiconductors ...
Page 400: ...MC9S08PA4 Reference Manual Rev 5 08 2017 400 NXP Semiconductors ...