AN2417 Freescale Semiconductor / Motorola, AN2417 Datasheet - Page 7

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

The duration of the access cycle is controlled by either the wait signal or the setting of programmable wait
state. If wait signal is used to control the access cycle length, DTACK should be enabled and select as
Compact Flash wait function. To enable DTACK, WSC bits (EIM_CS5H[45:40]) should be set as 0x3F.
Also bit 63 of Chip Select 5 Upper Control Register (EIM_CS5H[63]) should be set to configure DTACK
to support Compact Flash wait signal.
Note that if DTACK is enabled, the Compact Flash Card must assert the wait signal within 1024 system
clock cycle. Otherwise bus error will occur. Also only 16 bit access is can be used when DTACK is
enabled and CS5 is configured as 16 bit access. The EIM will not separate 32 bit access into two 16 bit
access when DTACK is enabled.
The duration of the access cycle can also be controlled by programmable wait state, that is the
configuration in the WSC bit (EIM_CS5H[45:40]). In this case, the WAIT signal is ignored and the access
cycle length is fixed by the WSC bit.
1.6.5 Card Detection
The CD1# and CD2# pins are connected to ground on the Compact Flash Card internally. They are used by
host to determine Compact Flash Card is fully inserted in the socket.
This two pin is input to a OR gate with pull up resistor. The output of OR gate is connected to GPIO PA20.
Card insertion can be detected whenever there is a high to low transaction in GPIO PA20. The power up
and reset process can then proceed.
The output is also used to enable the buffer between the DragonBall processor and the Compact Flash
interface.
MOTOROLA
IORD#, IOWR#
Signal Name
CE1#, CE2#
(IREQ in I/O
OE#, WE#,
READY
RESET
mode)
WAIT
Number
of Pin
Total
4
2
1
1
1
Freescale Semiconductor, Inc.
Directio
For More Information On This Product,
Signal
Output
Output
Input
Input
Input
n of
MC9328MX1/MXL Application Note
Engineering Draft / Preliminary
Go to: www.freescale.com
In memory mode, OE is used to
read data and WE used to write
data to Compact Flash
In I/O mode, IORD and IOWR is
used instead of OE and WR
Use to select the card and to
indicate whether a byte or word
operation is being performed.
Indicate CF card is ready to
accept new data transfer
Perform a hardware reset to
compact flash card, usually
asserted only at power up
Signal the host to delay
completion of a memory or I/O
cycle that is in progress
Table 5.
Function
Output from MC9328MX1/MXL
processor OE and WE signal
connect to glue logic
CS[5], EB3 and EB2 is connected
to glue logic, which output CE1#
and CE2# signals
Connect to GPIO PA18 through
buffer
Connect to GPIO PB17 through
buffer
Connect to DTACK through buffer
Connection to MX1
Introduction
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