Use Cases
980
SPNU503C – March 2018
Copyright © 2018, Texas Instruments Incorporated
High-End Timer Transfer Unit (HTU) Module
32-Bit-Transfer of data fields:
shows how the internal element counter, frame counter and the address registers change over
time for the example described above. Every time the PCNT instruction captures a new value it generates
a request to the HTU, which starts a frame. At the end of each frame the frame counter decrements.
(1)
Shows the byte addresses
Table 21-6. 32-Bit-Transfer of Data Fields
(1)
Frame Counter
3
2
1
Element Counter
3
2
1
3
2
1
3
2
1
Source Address (HET)
38h
48h
58h
38h
48h
58h
38h
48h
58h
Destination Address (main CPU RAM)
70h
74h
78h
7Ch
80h
84h
88h
8Ch
90h
The destination buffer is filled with the WCAP, ECNT, and PCNT data field values as shown in
.
Table 21-7. Destination Buffer Values
Address
Frame Count
Instruction
Value
70h
3
WCAP
3
74h
3
ECNT
1
78h
3
PCNT
2
7Ch
2
WCAP
6
80h
2
ECNT
2
84h
2
PCNT
3
88h
1
WCAP
10
8Ch
1
ECNT
3
90h
1
PCNT
4
The corresponding setup of the HTU control packet for this example is as follows:
IHADDR
= 0x38
// points to WCAP data field
IFADDRA
= 0x70
// points to buffer
ITCOUNT [frame count = 3] [element count = 3]
IHADDRCT = [DIR: Read HET and write to full address]
[SIZE: 32 bit]
[ADDMH: Increment HET address by 16 bytes]
[ADDMF: Post increment full address mode]
[Any transfer mode]