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Registers
1575
SPRUH82C – April 2013 – Revised September 2016
Copyright © 2013–2016, Texas Instruments Incorporated
Universal Parallel Port (uPP)
32.3.18 uPP DMA Channel I Status 2 Register (UPIS2)
The uPP DMA channel I status register 2 (UPIS2) reports the status of the current DMA Channel I
transfer. The PEND bit is used to determine when a new transfer may be programmed into the uPP DMA
channel I descriptor registers (UPID
n
). The UPIS2 is shown in
and described in
Figure 32-33. uPP DMA Channel I Status 2 Register (UPIS2)
31
16
Reserved
R-0
15
8
7
4
3
2
1
0
Reserved
WM
Reserved
PEND
ACT
R-0
R-0
R-0
R-0
R-0
LEGEND: R = Read only; -
n
= value after reset
Table 32-28. uPP DMA Channel I Status 2 Register (UPIS2) Field Descriptions
Bit
Field
Value
Description
31-8
Reserved
0
Reserved
7-4
WM
0-Fh
DMA Watermark. When the associated interface channel operates in receive mode, this field records
the maximum FIFO block occupancy reached during any transaction. When the associated interface
channel operates in transmit mode, this field records the FIFO block emptiness and is overwritten every
uPP interface clock cycle.
3-2
Reserved
0
Reserved
1
PEND
DMA Transfer Pending. Reports whether another DMA transfer is pending for DMA Channel I. This field
must be low before another transfer may be programmed.
0
No transfer pending. Channel I descriptors may be written.
1
Transfer pending. Channel I descriptors may not be written.
0
ACT
DMA Active. Reports the current status of DMA Channel I. This field should not be used to determine
whether the DMA Channel I descriptors are programmable; use the PEND bit instead.
0
DMA is inactive.
1
DMA is active.