Intermec 073292-001 Benutzerhandbuch
Chapter 4 — Theory of Operation
PXA255 GPIO Signal Descriptions (continued)
PXA255 GPIO
Function
Signal Description
Usage
GP32
-SDMMC_WP
SD slot write protect
0 = write protect
1 = writes enabled
1 = writes enabled
GP38
-HCR_OE
HCR registers output enable. This signal floats high on cold
boot so that HCR register outputs float to their default-off states
(through pull-up and pull-down resistors). Once software has
initialized the HCR registers, software should enable the HCR
outputs by setting this bit low.
boot so that HCR register outputs float to their default-off states
(through pull-up and pull-down resistors). Once software has
initialized the HCR registers, software should enable the HCR
outputs by setting this bit low.
0 = HCR regs
low-Z
1 = HCR regs
high-Z
low-Z
1 = HCR regs
high-Z
GP48
-POE/PCI_IRQ
Mini PCI IRQ (CF slot OE if CF slot installed). PCI bridge
interrupts, PCI card interrupts and keypad interrupts all share
this line.
interrupts, PCI card interrupts and keypad interrupts all share
this line.
↓ = interrupt
GP66
KEY_DRV0
Keypad matrix column drive 0
0 = scan column
1 = idle
1 = idle
GP67
KEY_DRV1
Keypad matrix column drive 1
0 = scan column
1 = idle
1 = idle
GP68
KEY_DRV2
Keypad matrix column drive 2
0 = scan column
1 = idle
1 = idle
GP69
KEY_DRV3
Keypad matrix column drive 3
0 = scan column
1 = idle
1 = idle
GP70
KEY_DRV4
Keypad matrix column drive 4
0 = scan column
1 = idle
1 = idle
GP71
KEY_DRV5
Keypad matrix column drive 5
0 = scan column
1 = idle
1 = idle
GP72
KEY_DRV6
Keypad matrix column drive 6
0 = scan column
1 = idle
1 = idle
GP73
KEY_DRV7
Keypad matrix column drive 7
0 = scan column
1 = idle
1 = idle
GP79
PCI_SPARE
Spare I/O from FPGA. May be used as an interrupt, GPIO, or
additional chip select to the FPGA.
additional chip select to the FPGA.
GP80
-SD_PWR_EN
Power enable for SD slot
0 = SD power on
1 = SD power off
1 = SD power off
HCR Output Signal Descriptions
HCR
Bit
Function
Signal Description
Usage
U16
16
BT_PWR_EN*
Bluetooth module power enable
0 = on
1 = off
1 = off
U16
17
BLUE_LED
Blue System Light control
(moved from 0x1400_0000 bit 15)
(moved from 0x1400_0000 bit 15)
0 = LED off
1 = LED on
1 = LED on
U16
18
AUDIO_EN
Audio power supply enable
0 = off
1 = on
1 = on
U16
19
RESUME_EN
Resume Enable for non-I/O-key sources. This enables and
disables system resume from the following events:
disables system resume from the following events:
- Tethered scanner trigger on 10-pin port (SCAN_TRIG)
- Tethered scanner trigger on 26-pin port (DOCK_TRIG)
- Dock serial DCD
- USB host present
- Tethered scanner trigger on 26-pin port (DOCK_TRIG)
- Dock serial DCD
- USB host present
Note that SCAN_PWR_EN must be asserted for SCAN_TRIG
to wake the system through this mechanism. Similarly,
DOCK_EN must be asserted for DOCK_TRIG to wake the
system. Dock DCD and USB need no other enable.
to wake the system through this mechanism. Similarly,
DOCK_EN must be asserted for DOCK_TRIG to wake the
system. Dock DCD and USB need no other enable.
0 = disable resume
1 = enable resume
1 = enable resume
CK30 Handheld Computer Service Manual
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