AN2417 Freescale Semiconductor / Motorola, AN2417 Datasheet - Page 5

• Manufacturer Part Number: AN2417
• Description: PCMCIA and Compact Flash Interface for the MC9328MX1 and MC9328MXL Application Processors Application Note
• Manufacturer: Freescale Semiconductor / Motorola

1.6 Signal Description (Compact Flash)
1.6.1 Power Signal
The voltage supply circuit is implemented by a PMOS FET transistor. VS1# is connected to the gate of the
PMOS FET with pull up resistor. If the Card support 3.3 V voltage, the VS1# pin is internally grounded
inside the CF card, and VCC will have 3.3V voltage supply. 5V voltage supply is not supported.
1.6.2 Address Bus
Compact Flash address bus width is 11 bit. The address bus is connected to DragonBall MX Processor
lower 11 bit address bus through a unidirectional buffer.
The REG# signal is used to separate attribute memory address space from common memory address space.
When REG# signal is asserted, the address refers to attribute memory address space. Since Compact Flash
need only 11 address pins and CS5 can support up to 24 address pin, the REG# signal is implemented by
A22.
1.6.3 Data Bus
The data bus is connected to DragonBall MX databus through bi-directional buffer. The buffer is enable
only when access cycle is active (CS5 is asserted). RW signal from CS5 indicate whether it is a read or
write access cycle. This signal is latched by a D flipflop and connected to buffer direction control.
MOTOROLA
A0 - A10
Signal
Name
REG#
D0 - D15
VS1# VS2#
Signal
Name
Signal
Name
GND
VCC
Number of
Total
Total Number
Pin
11
4
Total Number
of Pin
16
of Pin
1
4
2
Freescale Semiconductor, Inc.
Direction of
For More Information On This Product,
Signal
Input
Input
MC9328MX1/MXL Application Note
Bi Directional
Direction of
Direction of
Engineering Draft / Preliminary
Signal
Ground
Signal
Output
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DC in
Use to Distinguish between
attribute memory and
common memory
Table 1.
Table 2.
Table 3.
Address Bus
Function
Supply Voltage
Voltage Sense
Function
Function
Ground
Data Bus
Connection to MC9328MX1/MXL
databus bus through buffer
Connect to Power Supply Circuit
Connect to Ground
Vs1 Connect to power supply circuit
Vs2 not connected
Connection to MC9328MX1/MXL
address bus A[10:0] through buffer
Connect to MC9328MX1/MXL A22
through buffer
Connection to MX1
Connection to MX1
Connection to MX1
Introduction
5