Multichannel Selection Operation
11-69
Multichannel Buffered Serial Ports
Figure 11–46.
Multichannel Control Register
31
25
24
23
22
21
20
18
17
16
rsvd
XPBBLK
XPABLK
XCBLK
XMCM
R, +0000 000
RW, +00
RW, +00
R, +000
RW, +00
15
9
8
7
6
5
4
2
1
0
rsvd
RPBBLK
RPABLK
RCBLK
rsvd
RMCM
R, +0000 000
RW, +00
RW, +00
R, +000
R, +0
RW, +0
Table 11–19. Multichannel Control Register Field Descriptions
Name
Function
Section
RMCM
Receive multichannel selection enable
RMCM = 0: All channels are enabled.
RMCM = 1: All elements are disabled. Required channels are selected by enabling
RP(A/B)BLK and RCER appropriately.
11.6.2
XMCM
Transmit multichannel selection enable
XMCM = 00b: All elements are enabled without masking (DX is always driven during
transmission of data). DX is masked or driven to hi-Z during inter-
packet intervals, when a channel is masked (regardless of whether
it is enabled), or when an element is disabled.
XMCM = 01b: All elements are disabled and therefore masked by default. Required
elements are selected by enabling XP(A/B)BLK and XCER appropri-
ately and these selected elements are not masked, DX is always driv-
en.
XMCM = 10b: All elements are enabled but masked. Selected elements that are en-
abled via XP(A/B)BLK and XCER are unmasked.
XMCM = 11b: All elements are disabled and therefore masked by default. Required
elements are selected by enabling RP(A/B)BLK and RCER appropri-
ately. Selected elements can be unmasked by RP(A/B)BLK and
XCER. This mode is used for symmetric transmit and receive opera-
tion. (See section 11.6.3 for more details on symmetric operation).
11.6.3