MSC8144E Reference Manual, Rev. 3
6-14
Freescale
Semiconductor
Boot Program
6.
Checksum. A 2-byte field that holds the XOR of all previous data (Block Control and
on). The boot code XORs each received 2 bytes with the previous checksum value and
verifies the validation by comparing it to this field.
7.
Checksum. A 2-byte field that holds bitwise-not of the Checksum.
The I
2
C bootloader expects the 4 bytes of Checksum and Checksum regardless of the CSE value.
If the Checksum is disabled, these 4 bytes are not checked. By using Checksum and Checksum,
the boot ensures that all values of the bits are real values and that there are no stuck signals. If
both Checksum and Checksum are erroneous in a block, core 0 enters the debug state.
The SCL frequency is set as closely to 400KHz as possible, as mentioned in Section 6.4.1. For
each block, the Software I
2
C read access begins with the boot code driving the device select and
2 bytes of address, followed by a RESTART condition. The I
2
C slave drives its data (beginning
with the Block Control byte) until the end of the block. The last byte of each block is not
acknowledged by the MSC8144. After the ninth unacknowledged bit, the boot code generates a
STOP condition. Figure 6-6 describes the Software I
2
C read access.
6.5.2 Ethernet
The MSC8144E device can load files through the Ethernet port using DHCP (Dynamic Host
Configuration Protocol) and TFTP (Trivial File Transfer Protocol).
Supports RGMII and SGMII @1000 Mbps full duplex connected to a SWITCH
(MAC-to-MAC).
Supports RGMII, RMII, and SMII @100 Mbps full duplex connected to a SWITCH
(MAC-to-MAC).
For DHCP, each client must have its own unique MAC (Media Access Control) address.
This MAC address can be based on RCWHR[DEVID] or be user-defined.
This DHCP implementation supports IPv4.
Figure 6-6. I
2
C Read Access
A
0
A
1
A
2
DEVICE SELECT
ST
A
R
T
BYTE ADDR
A
8
A
7
A
4
A
3
A
5
A
6
A
9
A
10
BYTE ADDR
A
16
A
15
A
12
A
11
A
13
A
14
A
17
A
18
R/W
ACK
ACK
A
0
A
1
A
2
DEVICE SELECT
ST
A
R
T
ACK
R/W
ACK
ACK
NO ACK
ST
OP
ACK
Note: A
0
and D
0
are the most significant bits.
1
1
0
0
1 0 1 0
DATA OUT 1
D
5
D
4
D
1
D
0
D
2
D
3
D
7
D
6
DATA OUT N
D
5
D
4
D
1
D
0
D
2
D
3
D
7
D
6
ST
O
P
Summary of Contents for MSC8144E
Page 1: ...MSC8144E Reference Manual Quad Core Media Signal Processor MSC8144ERM Rev 3 July 2009 ...
Page 48: ...MSC8144E Reference Manual Rev 3 xlviii Freescale Semiconductor ...
Page 86: ...MSC8144E Reference Manual Rev 3 1 38 Freescale Semiconductor Overview ...
Page 168: ...MSC8144E Reference Manual Rev 3 3 60 Freescale Semiconductor External Signals ...
Page 242: ...MSC8144E Reference Manual Rev 3 5 26 Freescale Semiconductor Reset ...
Page 314: ...MSC8144E Reference Manual Rev 3 8 24 Freescale Semiconductor General Configuration Registers ...
Page 414: ...MSC8144E Reference Manual Rev 3 10 14 Freescale Semiconductor MSC8144E SC3400 DSP Subsystem ...
Page 452: ...MSC8144E Reference Manual Rev 3 11 38 Freescale Semiconductor Internal Memory Subsystem ...
Page 520: ...MSC8144E Reference Manual Rev 3 12 68 Freescale Semiconductor DDR SDRAM Memory Controller ...
Page 1070: ...MSC8144E Reference Manual Rev 3 21 28 Freescale Semiconductor Timers ...