(
)
1
E C P D I V
N
V C L K o r O S C I
E C L K
+
=
System and Peripheral Control Registers
208
SPNU563A – March 2018
Copyright © 2018, Texas Instruments Incorporated
Architecture
2.5.2.3
ECP Control Register 1 (ECPCNTL1)
The ECP register, shown in
and described in
, configures the ECLK2 pin in
functional mode.
NOTE:
ECLK2 Functional mode configuration.
The ECLK2 pin must be placed into Functional mode by setting the ECPCLKFUN bit to 1 in
the SYSPC1 register before a clock source will be visible on the ECLK pin.
Figure 2-61. ECP Control Register 1 (ECPCNTL1) (offset = 28h)
31
28
27
25
24
23
22
16
ECP_KEY
Reserved
ECPSSEL
ECPCOS
Reserved
R/WP-5h
R-0
R/W-0
R/W-0
R-0
15
0
ECPDIV
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -
n
= value after reset
Table 2-74. ECP Control Register 1 (ECPCNTL1) Field Descriptions
Bit
Field
Value
Description
31-28
ECP_KEY
Enable ECP clock logic for ECLK2.
Ah
Clock functionality of ECP clock is enabled.
Others
Clock functionality of ECP clock is disabled.
27-25
Reserved
0
Reads return 0. Writes have no effect.
24
ECPSSEL
This bit allows the selection between VCLK and OSCIN as the clock source for ECLK2.
0
VCLK is selected as the ECP clock source.
1
OSCIN is selected as the ECP clock source.
23
ECPCOS
ECP continue on suspend.
Note: Suspend mode is entered while performing certain JTAG debugging operations.
0
ECLK output is disabled in suspend mode. ECLK output will be shut off and will not be seen on
the I/O pin of the device.
1
ECLK output is not disabled in suspend mode. ECLK output will not be shut off and will be seen
on the I/O pin of the device.
22-16
Reserved
0
Reads return 0. Writes have no effect.
15-0
ECPDIV
0-FFFFh
ECP divider value. The value of ECPDIV bits determine the external clock (ECP clock) frequency
as a ratio of VBUS clock or OSCIN as shown in the formula: