Phytec phyCORE-PXA255, Руководство по оборудованию

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Memory Configuration
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PHYTEC Meßtechnik GmbH 2004 L-657e_0
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The CF interface is separated from the data, address and control bus
by line driver circuits. The drivers for the data bus can be activated
with the signal CFOE. CFON activates the drivers for the address and
control signal outputs and CFIN activates the drivers for the input
signals such as IRQ.
REG ADDR D7 D3 D2 D1 D0
CF3 0x3001006 Res CFCD CFIN CFON CFOE
RW R/W=0 R/W R/W R/W R/W
Table 30: CF Card Control Register 3
CFOE Turns on the data bus line driver.
CFON Turns on the address bus and contol line driver.
CFIN Turns on the line driver for input signals.
CFCD Turns on the line driver with the CF card control
output signals such as CD1/2 etc.
CF control register 4 configures the supply voltage for the CF card
interface. The register bit 5 V/3 V is used to configure the CF card
voltage. If the bit is set to ’1’ the CF card is supplied with 5 V, if the
bit is set to ’0’ then the CF card is supplied with 3.3 V. If CFPWR is
set then the configured voltage (5 V or 3.3 V) is connected to the CF
card. In response the CF5V bit will be set for a 5 V supply voltage or
CF3V if a 3.3 V supply is used.
REG ADDR D7 D3 D2 D1 D0
CF4 0x3001008 Res CF5V CF3V 5V/3V CFPWR
RW R/W=0 R R R/W R/W
Table 31: CF Card Control Register 4
CFPWR Turns on the selected CF card voltage.
5V/3V Selects the CF card voltage; 1 = 5 V, 0 = 3.3 V
CF3V Indicates 3.3 V supply active.
CF5V Indicates 5 V supply active.