Freescale Semiconductor MPC5200B ユーザーズマニュアル

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MPC5200B Users Guide, Rev. 1
10-26
Freescale Semiconductor
Registers
10.3.3.1.4
Tx Enables PCITER(RW)—MBAR + 0x380C
msb  0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
R
RC
RF
Rsvd
CM
BE
Reserved
ME
Reserved
FEE
SE
RE
TAE
IAE
NE
W
RESET
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31 lsb
R
Reserved
W
RESET
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bits
Name
Description
0
Reset
Controller
(RC)
User writes this bit high to put Transmit Controller in a reset state. Other register bits are not 
affected. This Reset is intended for recovery from an error condition or to reload the Start 
Address when Continuous mode is selected. This Reset bit does not prohibit register 
access but it must be negated in order to initiate a Restart sequence (i.e. writing the 
Packet_Size register). If it is used to reload a Start Address then the Start_Add register must 
be written prior to asserting this Reset bit.
1
Reset
FIFO
(RF)
The FIFO will be reset and flushed of any existing data when set high. The Reset Controller 
bit and the Reset FIFO bit operate independently but clearly both must be low for normal 
operation.
2
Reserved
Unused bit. Software should write a zero to this bit.
3
Continuous
mode
(CM)
User writes this bit high to activate Continuous mode. In Continuous mode the Start_Add 
value is ignored at each packet restart and the PCI address is auto-incremented from one 
packet to the next. Also, the Packets_Done status byte will become active, indicating how 
many packets have been transmitted since the last Reset Controller condition. If the 
Continuous bit is low, software is responsible for updating the Start_Add value at each 
packet Restart.
4
Bus error
Enable
(BE)
User writes this bit high to enable Bus Error indications. 
 for Bus Error descriptions. Normally this bit will be low 
(negated) since illegal Slave bus accesses are not destructive to register contents (although 
it may indicate broken software). This bit does not affect interrupt generation.
5:6
Reserved
Unused. Software should write zero to these bits.
7
Master
Enable
(ME)
This is the Transmit Controller master enable signal. User must write it high to enable 
operation. It can be toggled low to permit out-of-order register updates prior to generating 
a Restart sequence (in which case transmission will begin when Master Enable is written 
back high), but it should not be used as such in Continuous mode because it has the side 
effect of resetting the Packets_Done status counter.
8:9
Reserved
Unused. Software should write zero to these bits.
10
FIFO Error
Enable
(FEE)
User writes this bit high to enable CPU Interrupt generation in the case of FIFO error 
termination of a packet transmission. It may be desirable to mask CPU interrupts in the case 
that Multi-Channel DMA is controlling operation, but in such a case software should poll the 
status bits to prevent a possible lock-up condition.
11
System error
Enable
(SE)
User writes this bit high to enable CPU Interrupt generation in the case of system error 
termination of a packet transmission. It may be desirable to mask CPU interrupts in the case 
that Multi-Channel DMA is controlling operation, but in such a case someone should be 
polling the status bits to prevent a possible lock-up condition.