Intermec CK30 Service Manual page 55

PXA255 GPIO Signal Descriptions (continued)
PXA255 GPIO Function
GP32 -SDMMC_WP
GP38 -HCR_OE
GP48 -POE/PCI_IRQ
GP66 KEY_DRV0
GP67 KEY_DRV1
GP68 KEY_DRV2
GP69 KEY_DRV3
GP70 KEY_DRV4
GP71 KEY_DRV5
GP72 KEY_DRV6
GP73 KEY_DRV7
GP79 PCI_SPARE
GP80 -SD_PWR_EN
HCR Output Signal Descriptions
HCR Bit Function
U16 16 BT_PWR_EN*
U16 17 BLUE_LED
U16 18 AUDIO_EN
U16 19 RESUME_EN
CK30 Handheld Computer Service Manual
Signal Description
SD slot write protect
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.
Mini PCI IRQ (CF slot OE if CF slot installed). PCI bridge
interrupts, PCI card interrupts and keypad interrupts all share
this line.
Keypad matrix column drive 0
Keypad matrix column drive 1
Keypad matrix column drive 2
Keypad matrix column drive 3
Keypad matrix column drive 4
Keypad matrix column drive 5
Keypad matrix column drive 6
Keypad matrix column drive 7
Spare I/O from FPGA. May be used as an interrupt, GPIO, or
additional chip select to the FPGA.
Power enable for SD slot
Signal Description
Bluetooth module power enable
Blue System Light control
(moved from 0x1400_0000 bit 15)
Audio power supply enable
Resume Enable for non-I/O-key sources. This enables and
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
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.
Chapter 4 — Theory of Operation
Usage
0 = write protect
1 = writes enabled
0 = HCR regs
low-Z
1 = HCR regs
high-Z
↓ = interrupt
0 = scan column
1 = idle
0 = scan column
1 = idle
0 = scan column
1 = idle
0 = scan column
1 = idle
0 = scan column
1 = idle
0 = scan column
1 = idle
0 = scan column
1 = idle
0 = scan column
1 = idle
0 = SD power on
1 = SD power off
Usage
0 = on
1 = off
0 = LED off
1 = LED on
0 = off
1 = on
0 = disable resume
1 = enable resume
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