MC94MX21DVKN3 Freescale, MC94MX21DVKN3 Datasheet - Page 22

• Manufacturer Part Number: MC94MX21DVKN3
• Manufacturer: Freescale

Specifications of MC94MX21DVKN3

• Operating Temperature (max): 70C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Compliant

Specifications
3.8.1.1.2
Figure 7
CS BMI checks the BMI_WRITE logic level to determine if the current cycle is a write cycle. If the BMI_
WRITE is logic low, it latches data into the RxFIFO on each falling edge of BMI_CLK/CS signal.
Note: All timings assume that the hclk is running at 133 MHz.
Note: At this mode, the maximum frequency of the BMI_CLK/CS can be up to 36 MHz (doubles as maximum data pad speed).
3.8.1.2
In this mode MMD_MODE_SEL and MMD_CLKOUT are both set. The software must know which
mode it is now (READ or WRITE). When the BMI_WRITE is high, BMI drives BMI_CLK/CS out if the
TxFIFO is not emptied. When BMI_WRITE is low, user can write a 1 to READ bit of control register1 to
issue a write cycle (MMD write BMI).
3.8.1.3
Figure 13
is high, the BMI drives BMI_CLK/CS out if data is written to TxFIFO (BMI_READ_REQ become high),
BMI puts data into data bus and enable data out on the rising edge of BMI_CLK/CS. The MMD devices
can latch the data on each falling edge of BMI_CLK/CS.
It is recommended that the MMD do not change the BMI_WRITE signal from high to low when the
BMI_READ_REQ is asserted. If user writes data to the TxFIFO when the BMI_WRITE is low, the BMI
will drive BMI_CLK/CS out once the BMI_WRITE is changed from low to high.
22
BMI_CLK/CS
BMI_READ_REQ
BMI_D[15:0]
BMI_WRITE
shows the MMD write BMI timing when MMD drives clock. On each falling edge of BMI_CLK/
shows the MMD read BMI timing when BMI drives the BMI_CLK/CS. When the BMI_WRITE
BMI Drives the BMI_CLK/CS
MMD Read BMI Timing
receive data setup time
MMD Write BMI Timing
write setup time
write hold time
(MMD_MODE_SEL=1, MASTER_MODE_SEL=0, MMD_CLKOUT=0)
Item
Figure 7. MMD (ATI) Drives Clock, MMD Write BMI Timing
Can be asserted any time
Ts
Table 14. MMD Write BMI Timing
MC94MX21 Technical Data, Rev. 1.5
Symbol
Tds
Th
Ts
RxD1
Tds
Minimum
RxD2
11
0
5
Typical
–
–
–
Can be asserted any time
Maximum
Last RxD
–
–
–
Th
Freescale Semiconductor
Unit
ns
ns
ns