ENC624J600-I/PT Microchip Technology, ENC624J600-I/PT Datasheet - Page 36

• Manufacturer Part Number: ENC624J600-I/PT
• Description: IC ETHERNET CTRLR W/SPI 64-TQFP
• Manufacturer: Microchip Technology

Specifications of ENC624J600-I/PT

• Package / Case: 64-TFQFP
• Controller Type: Ethernet Controller
• Interface: SPI
• Voltage - Supply: 3 V ~ 3.6 V
• Current - Supply: 96mA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Input Voltage Range (max): 5.5 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Operating Supply Voltage: 3 V to 3.6 V
• Supply Current (max): 117 mA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AC164132 - BOARD DAUGHTER PICTAIL ETHERNET
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

ENC424J600/624J600
3.5.5
Indirect access to the SRAM buffer is available to all I/O
interfaces. For the SPI interface, it is the only method
available. For PSP interfaces, it may be used in
addition to the direct access method.
Three separate pointer pairs are available for the host
microcontroller to use when accessing the SRAM:
• General Purpose Buffer Read/Write Pointer
• Receive Buffer Read/Write Pointer
• User-Defined Area Read/Write Pointer
Each of these pointer pairs provides an 8-bit virtual
window register (EGPDATA, ERXDATA and EUDATA)
through which the SRAM data is read or written. The
pointers and their associated data windows are shown
in Figure 3-5.
FIGURE 3-5:
DS39935C-page 34
(EGPRDPT/EGPWRPT)
(ERXRDPT/ERXWRPT)
(EUDARDPT/EUDAWRPT)
INDIRECT SRAM BUFFER ACCESS
POINTERS FOR INDIRECT BUFFER ACCESS
Data Windows
EUDADATA
EGPDATA
ERXDATA
Read
Write
Read
Read
Write
Write
General Purpose
Circular RX FIFO
Unimplemented
EGPDATA, ERXDATA and EUDADATA are all 8 bits
wide. When writing to them using a 16-bit PSP
interface, the low-order byte select or write enable must
be used; strobing the high byte Byte Select or Write
Enable has no effect. When reading from a 16-bit PSP
interface, one byte of useful data will be returned on the
lower 8 bits of the data bus; the upper 8 bits are to be
ignored.
When a data window register is read, the memory
contents at the address indicated by the corresponding
Read Pointer are obtained and presented to the host
microcontroller. Similarly, when a data window register
is written, the memory contents at the address
indicated by the corresponding Write Pointer are
updated by the data from the host microcontroller.
Following a read/write operation, the appropriate
pointer is automatically incremented in hardware.
EUDADATA
EUDADATA
EGPDATA
EGPDATA
ERXDATA
ERXDATA
Buffer
Buffer
Buffer Pointers
0000h
ERXRDPT
5FFFh
EGPWRPT
ERXWRPT
EUDARDPT
EUDAWRPT
ERXST – 1
ERXST
EGPRDPT
EUDAST
EUDAND
 2010 Microchip Technology Inc.