mk50h27 STMicroelectronics, mk50h27 Datasheet - Page 21

• Manufacturer Part Number: mk50h27
• Description: Signalling System 7 Link Controller
• Manufacturer: STMicroelectronics

4.1.2.5 Control and Status Register 4 (CSR4)
CSR4 allows redefinition of the bus master interface.
RAP<3:1> = 4
BIT
15:12
11:10
09:08
07
06
05
NAME
XWD0/1, RWD0/1
0
FWM
BAE
BUSR
BSWPC
X
W
D
1
1
5
1
4
X
W
D
0
R
W
D
1
1
3
1
2
R
W
D
0
Receive Watchdog Timers. These timers are independently program-
mable and are reset by any transition on the TCLK and RCLK pins re-
spectively. The Watchdog timers will expire after approximately Wn
SYSCLK cycles (if not reset by transition on TCLK / RCLK pins) and
Provider Primitive 3 or 4 will be issued. The following table shows the
selections for Wn:
the MK50H27 from performing DMA transfers to/from the data buffers
until the FIFOs contain a minimum amount of data or space for data.
For receive
after the FIFO has at least N 16-bit words or an end of
has
only be transferred from the data buffers when the transmit FIFO
has room for at least N words of data. N is defined as follows:
by the MK50H27 constantly providing the ability to use A23-A20 for
memory bus selection. If clear, A23-A20 behave identically to A19-
A16.
then pin 15 is either BM0 or BYTE depending on bit 00.
information see the description for pin 15 in this document. BUSR
is READ/WRITE and cleared on bus Reset.
DESCRIPTION
These bits enable and determine the timer values for the Transmit and
Reserved, must be written as zero.
These bits define the FIFO watermarks. FIFO watermarks prevent
Bus Address Enable: if BAE is set then the A23-A20 pins are driven
If this bit is set, pin 15 becomes input BUSREL. If this bit is clear
This bit determines the byte ordering of all ”non-data” DMA transfers.
XWD1/RWD1
1
1
0
0
0
1
1
1
0
0
been
0
9
W
M
F
data, data will only be transferred to the data buffers
FWM<1:0>
0
8
11
10*
01
00
reached. Conversely, for transmit data, data will
0
7
B
A
E
XWD0/RWD0
* Suggested setting
0
6
B
U
S
R
0
5
B
S
W
P
C
0
1
0
1
0
4
B
U
R
S
T
0
3
0
1
:
1 word
9 words
17 words
25 words
N
0
2
B
S
W
P
D
0
1
A
C
O
N
Disabled
2
2
2
Wn
18
19
20
0
0
B
C
O
N
signal unit
MK50H27
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