MCF5272VF66 Freescale, MCF5272VF66 Datasheet - Page 249

• Manufacturer Part Number: MCF5272VF66
• Manufacturer: Freescale

Specifications of MCF5272VF66

• Family Name: MCF5xxx
• Device Core: ColdFire
• Device Core Size: 32b
• Frequency (max): 66MHz
• Instruction Set Architecture: RISC
• Supply Voltage 1 (typ): 3.3V
• Operating Temp Range: 0C to 70C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Pin Count: 196
• Package Type: MA-BGA
• Lead Free Status / RoHS Status: Not Compliant

11.5.20 Pointer-to-Transmit Descriptor Ring (ETDSR)
This register provides a pointer to the start of the circular transmit buffer descriptor queue in external
memory. This pointer must be long-word aligned. However, it is recommended it be aligned on a 16 byte
boundary (address evenly divisible by 16) in order to improve bus utilization. Bits 1 and 0 should be set
to 0 by the user. Non-zero values in these two bit positions are ignored by the hardware.
This register is not reset and must be initialized by the user prior to operation.
Freescale Semiconductor
31–2
Bits
1–0
Reset
Reset
Field
Field
Addr
R/W
R/W
31
15
X_DES_START
Name
—
MCF5272 ColdFire
Figure 11-25. Pointer-to-Transmit Descriptor Ring (ETDSR)
Reserved, should be cleared.
Pointer to start of transmit buffer descriptor queue.
Table 11-28. ETDSR Field Descriptions
®
Integrated Microprocessor User’s Manual, Rev. 3
X_DES_START
X_DES_START
MBAR + 0xC14
Read/Write
Read/Write
Undefined
Undefined
Description
2
0
Ethernet Module
1
16
0
0
11-31