MC9328MX21VG Freescale, MC9328MX21VG Datasheet - Page 19

• Manufacturer Part Number: MC9328MX21VG
• Manufacturer: Freescale

Specifications of MC9328MX21VG

• Operating Temperature (min): 0C
• Operating Temperature (max): 70C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Not Compliant

3.7
The External DMA request is an active low signal to be used by devices external to i.MX21 processor to
request the DMAC for data transfer.
After assertion of External DMA request the DMA burst will start when the channel on which the External
request is the source (as per the RSSR settings) becomes the current highest priority channel. The external
device using the External DMA request should keep its request asserted until it is serviced by the DMAC.
One External DMA request will initiate one DMA burst.
Freescale Semiconductor
Ref
No.
1
2
3
4
5
6
RESET_OUT
Width of input POWER_ON_RESET
Width of internal POWER_ON_RESET
(CLK32 at 32 kHz)
7k to 32k-cycle stretcher for SDRAM reset
14k to 32k-cycle stretcher for internal system reset HRESERT
and output reset at pin RESET_OUT
Width of external hard-reset RESET_IN
4k to 32k-cycle qualifier
RESET_IN
HRESET
External DMA Request and Grant
CLK32
HCLK
6
Parameter
Figure 3. Timing Relationship with RESET_IN
Table 12. Reset Module Timing Parameters
MC9328MX21 Technical Data, Rev. 3.4
5
1.8 V ± 0.10 V 3.0 V ± 0.30 V
Min
800
300
14
7
4
4
Max
300
14
–
7
–
4
14 cycles @ CLK32
Min
800
300
14
7
4
4
4
Max
300
14
–
7
–
4
Cycles of CLK32
Cycles of CLK32
Cycles of CLK32
Cycles of CLK32
Specifications
Unit
ms
ms
19