Registers
1556
SPRUH82C – April 2013 – Revised September 2016
Copyright © 2013–2016, Texas Instruments Incorporated
Universal Parallel Port (uPP)
32.3.2 uPP Peripheral Control Register (UPPCR)
The uPP peripheral control register (UPPCR) controls certain peripheral-level configuration settings for the
uPP peripheral. Among these are global enable and reset states and rules governing its behavior during
CPU emulation halt. This register also reports the current activity state of the uPP internal DMA controller.
The UPPCR is shown in
and described in
Figure 32-17. uPP Peripheral Control Register (UPPCR)
31
16
Reserved
R-0
15
8
7
6
5
4
3
2
1
0
Reserved
DB
Reserved
SWRST
EN
RTEMU
SOFT
FREE
R-0
R-0
R-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -
n
= value after reset
Table 32-12. uPP Peripheral Control Register (UPPCR) Field Descriptions
Bit
Field
Value
Description
31-8
Reserved
0
Reserved
7
DB
DMA burst status. Used to poll whether internal DMA is currently active. Writes to this field have no
effect.
0
Internal DMA is idle.
1
Internal DMA is active.
6-5
Reserved
0
Reserved
4
SWRST
Software reset control. Asserting reset clears internal state machines and prevents device from running.
For graceful reset, you should first clear the EN bit and poll the DB bit to make sure the DMA is idle,
then assert the SWRST bit.
0
Peripheral running (out of reset)
1
Peripheral in reset
3
EN
Peripheral enable control. When transitioning to disabled status, peripheral completes any DMA
transactions already in progress before stopping.
0
Peripheral is disabled.
1
Peripheral is enabled.
2
RTEMU
Real-time emulation control. When asserted, emulation halts/breakpoints halts pending transactions.
0
Real-time emulation disabled. Peripheral continues pending transactions while program is halted.
1
Real-time emulation enabled. Peripheral halts transactions while program is halted.
1
SOFT
Soft stop enable. Must be enabled to allow emulation to halt the peripheral.
0
Soft stop is disabled.
1
Soft stop is enabled.
0
FREE
Enable free run. This must be disabled to allow emulation to halt the peripheral.
0
Free run is disabled.
1
Free run is enabled.