M68ICS08GR datasheet(209/408 Pages) FREESCALE

209 / 408 page

Input/Output Ports (I/O)

Port A

MC68HC908GR8 — Rev 4.0

Technical Data

MOTOROLA

Input/Output Ports (I/O)

209

16.3 Port A

Port A is an 4-bit special-function port that shares all four of its pins with

the keyboard interrupt (KBI) module. Port A also has software

configurable pullup devices if configured as an input port.

16.3.1 Port A Data Register

The port A data register (PTA) contains a data latch for each of the four

port A pins.

PTA3–PTA0 — Port A Data Bits

These read/write bits are software programmable. Data direction of

each port A pin is under the control of the corresponding bit in data

direction register A. Reset has no effect on port A data.

KBD3–KBD0 — Keyboard Inputs

The keyboard interrupt enable bits, KBIE3–KBIE0, in the keyboard

interrupt control register (KBICR) enable the port A pins as external

interrupt pins. See Keyboard Interrupt (KBI).

Address:

$0000

Bit 7

654321

Bit 0

Read:

0000

PTA3

PTA2

PTA1

PTA0

Write:

Reset:

Unaffected by reset

Alternate

Function:

KBD3

KBD2

KBD1

KBD0

Figure 16-2. Port A Data Register (PTA)

Freescale Semiconductor, Inc.

For More Information On This Product,

Go to: www.freescale.com

M68ICS08GR Datasheet(PDF) 209 Page - Freescale Semiconductor, Inc

M68ICS08GR Datasheet(HTML) 209 Page - Freescale Semiconductor, Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL