Register 7: EPI General-Purpose Configuration (EPIGPCFG), offset 0x010
Important:
The
MODE
field in the
EPICFG
register determines which configuration register is
accessed for offsets 0x010 and 0x014.
To access
EPIGPCFG
, the
MODE
field must be 0x0.
The General-Purpose configuration register is used to configure the control, data, and address pins.
This mode can be used for custom interfaces with FPGAs, CPLDs, and for digital data acquisition
and actuator control. Note that this register is reset when the
MODE
field in the
EPICFG
register is
changed. If another mode is selected and the General-purpose mode is selected again, the register
the values must be reinitialized.
This mode is designed for 3 general types of use:
■ Extremely high-speed clocked interfaces to FPGAs and CPLDs, with 3 sizes of data and optional
address. Framing and clock-enable permit more optimized interfaces.
■ General parallel GPIO. From 1 to 32 pins may be written or read, with the speed precisely
controlled by the baud rate in the
EPIBAUD
register (when used with the NBRFIFO and/or the
WFIFO) or by rate of accesses from software or μDMA.
■ General custom interfaces of any speed.
The configuration allows for choice of an output clock (free running or gated), a framing signal (with
frame size), a ready input (to stretch transactions), read and write strobes, address of varying sizes,
and data of varying sizes. Additionally, provisions are made for splitting address and data phases
on the external interface.
EPI General-Purpose Configuration (EPIGPCFG)
Base 0x400D.0000
Offset 0x010
Type RW, reset 0x0000.0000
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
reserved
WR2CYC
reserved
FRMCNT
FRM50
reserved
CLKGATE
CLKPIN
RO
RO
RO
RW
RO
RO
RW
RW
RW
RW
RW
RO
RO
RO
RW
RW
Type
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Reset
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
DSIZE
reserved
ASIZE
reserved
RW
RW
RO
RO
RW
RW
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
Type
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Reset
Description
Reset
Type
Name
Bit/Field
Clock Pin
Description
Value
No clock output.
0
EPI0S31
functions as the EPI clock output.
1
The EPI clock is generated from the
COUNT0
field in the
EPIBAUD
register (as is the system clock which is divided down from it).
0
RW
CLKPIN
31
June 18, 2014
876
Texas Instruments-Production Data
External Peripheral Interface (EPI)