MK50H28N ST Microelectronics, Inc., MK50H28N Datasheet - Page 28

• Manufacturer Part Number: MK50H28N
• Description: Multi Logical Link Frame Relay Controller
• Manufacturer: ST Microelectronics, Inc.

MK50H28
4.2.1 Mode Register
The Mode Register allows alteration of the MK50H28’s operating parameters.
28/64
15:11
10:06
BIT
05
04
03
NUMBER OF FLAGS
IADR + 00
MFS<4:0>
DRFCS
DTFCS
NAME
FCSS
0
10
12
14
16
18
20
22
24
26
28
30
1
2
4
6
8
Minimum Frame Spacing defines the minimum number of flag sequences transmitted
between adjacent frames transmitted by the MK50H28. This only affects frames
transmitted by the MK50H28 and does not restrict the spacing of the
frames received by the MK50H28.
the number of flags transmitted at the beginning of the frame after CTS is driven
low (minus one for the trailing flag). See the following table for encoding of this field.
Reserved. Must be written as zeros.
Disable Receiver FCS (CRC). When DRFCS = 0, the receiver will extract and check the
FCS field at the end of each frame. When DRFCS = 1, the receiver continues to extract
the last 16 or 32 bits of each frame, depending on FCSS, but no check is performed to
determine whether the FCS is correct. If the received frame is an even number of
bytes, the first 16 bits of the FCS will be appended to the end (as indicated by MCNT) of
the receive buffer data.
Disable Transmitter FCS. When DTFCS=0, the transmitter will generate and append the
FCS to each signal unit. When DTFCS = 1, the FCS logic is disabled, and no FCS is
generated with transmitted frames. Setting DTFCS = 1 is useful in loopback testing for
checking the ability of the receiver to detect an incorrect FCS.
FCS Select. When FCSS = 1, a 16-bit FCS is selected otherwise a 32-bit FCS is used.
1
5
1
4
<4:0>
MFS
1
3
MFS<4:0>
1
0
2
4
9
18
5
11
22
12
25
19
7
15
31
30
1
2
1
1
1
0
0
0
9
0
0
8
0
NUMBER OF FLAGS
DESCRIPTION
When using RTS/CTS control this field defines
0
7
0
0
6
0
32
34
36
38
40
42
44
46
48
50
52
54
56
58
60
62
0
5
D
R
F
C
S
D
T
F
C
S
0
4
0
3
F
C
S
S
0
2
MFS<4:0>
28
24
17
3
6
13
27
23
14
29
26
21
10
20
8
16
<2:0>
LBACK
0
1
0
0