LM3S8G62 Datasheet, PDF (817/1096 Pages) Texas Instruments – Stellaris® LM3S8G62 Microcontroller

OBSOLETE: TI has discontinued production of this device.
Stellaris^® LM3S8G62 Microcontroller
header from the RX FIFO when the RX request occurs. The μDMA causes an interrupt when this
transfer is complete. Upon entering the interrupt handler, the packet length in the FIFO and the
Ethernet header are in a buffer and can be examined. Once the packet length is known, then another
μDMA transfer can be set up to transfer the remaining received packet payload from the FIFO into
a buffer. This transfer should be initiated by software. Another interrupt occurs when this transfer
is done.
Even though the TX channel generates a TX empty request, the recommended way to handle μDMA
transfers for transmitting packets is to set up the transfer from the buffer containing the packet to
the transmit FIFO, and then to initiate the transfer with a software request. An interrupt occurs when
this transfer is complete. For both channels, the "auto-request" transfer mode should be used. See
“Micro Direct Memory Access (μDMA)” on page 349 for more details about programming the µDMA
controller.
17.4
17.4.1
Initialization and Configuration
The following sections describe the hardware and software configuration required to set up the
Ethernet Controller.
Hardware Configuration
Figure 17-4 on page 817 shows the proper method for interfacing the Ethernet Controller to a
10/100BASE-T Ethernet jack.
Figure 17-4. Interface to an Ethernet Jack
Stellaris
Microcontroller
PF2/LED1
PF3/LED0
60
59
MDIO ⁵⁸
TXOP ⁴³
PF2/LED1
PF3/LED0
R3
10K
+3.3V
+3.3V
R4 R5
49.9 49.9
C2
C3
10pF 10pF
TXON ⁴⁶
RXIP ⁴⁰
RXIN ³⁷
R8 R9
49.9 49.9
+3.3V
C6
C7
10pF 10pF
C13
0.01UF
10/100BASE-T Ethernet Jack
P2
+3.3V
12 ^G+
R6
11 ^G-
330
3 1CT: 1
C4 +3.3V
5
0.1UF
4
TX+ ₁
TX- ₂
RX+ ₃
4
7 1CT: 1
C5 +3.3V
6
5
RX- ₆
7
8
0.1UF
8
R7 ^+3.3V _{2 Y-}
330
1
Y+
9 NC
10 GND
J3011G21DNL
The following isolation transformers have been tested and are known to successfully interface to
the Ethernet PHY layer.
■ Isolation Transformers
– TDK TLA-6T103
– TDK TLA-6T118
– Bel-Fuse S558-5999-46
– Halo TG22-3506ND
July 24, 2012
817
Texas Instruments-Production Data