adm6993 Infineon Technologies Corporation, adm6993 Datasheet - Page 29

• Manufacturer Part Number: adm6993
• Description: Adm6993/x Hdlc To Fast Ethernet Converter
• Manufacturer: Infineon Technologies Corporation

During Read operation, a 2-bit turn around (TA) time spacing between the register address field and data field is
provided for the SDIO to avoid contention. Following the turnaround time, a 32-bit data stream is read from or
written into the management registers of the ADM6993/X.
Figure 3
Figure 4
3.5.1
The SMI of ADM6993/X supports a preamble suppression mode. If the station management entity (i.e. MAC or
other management controller) determines that all devices which are connected to the same SDC/SDIO in the
system support preamble suppression, then the station management entity needs not generate preamble for each
management transaction. The ADM6993/X requires a single initialization sequence of 35 bits of preamble
following power-up/hardware reset. This requirement is generally met by pulling-up the resistor of SDIO. While the
ADM6993/X will respond to management accesses without preamble, a minimum of one idle bit between
management transactions is required.
When ADM6993/X detects that there is address match, then it will enable Read/Write capability for external
access. When an address is mismatched, then ADM6993/X will tri-state the SDIO pin.
3.5.2
The following 2 steps are for reading the data of EEPROM Register via SMI Interface.
Write the address of the desired EEPROM Register and READ command to SMI Register 04
EX. <35”1”s><01><01><00000><00100><10><000 0000000 000001 0000000000000000>
Read ADM6993/X Internal EEPROM mapping Reg.1
Register will be in bit [15:0].
EX. <35”1”s><01><10><00000><00100><z0><000 0000000 000000 1000001000001111>
Get ADM6993/X Internal EEPROM mapping Reg.1
Data Sheet
SDIO (STA)
(AD2109)
(STA)
SDIO
SDC
SDIO
SDC
Preamble
Preamble
z
z
SMI Read Operation
SMI Write Operation
Preamble Suppression
Read EEPROM Register via SMI Register
0
0
Start
Start
1
1
1
0
Opcode
Opcode
(Read)
(Write)
0
1
0
0
Unused
Unused
0
0
0
0
0
0
ID[1:0]
ID[1:0]
0
0
0
0
Register Address (5'h0 in this
Register Address (5'h0 in this
0
0
CMD ADDRESS DATA
example)
SMI Write Operation
CMD ADDRESS DATA
0
example)
0
SMI Read Operation
0
0
H
. value 820f.
0
0
H
29
. Read SMI Register 04. The data of desired EEPROM
z
1
TA
TA
0
0
0
0
0
0
1
0
0
1
0
Register Data (32'h13000000 in this Example)
Register Data (32'h13000000 in this Example)
0
1
0
1
1
0
1
0
0
0
0
~
~
Function Description
Rev 1.11, 2005-11-28
0
H
~
~
0
0
ADM6993/X
0
0
0
0
z
z