dsp56800e Freescale Semiconductor, Inc, dsp56800e Datasheet - Page 218

• Manufacturer Part Number: dsp56800e
• Description: 16-bit Digital Signal Controller Core
• Manufacturer: Freescale Semiconductor, Inc

Address Generation Unit
For long-word memory accesses:
Table 6-7 on page 6-25 shows how the M01 register is correctly programmed for long memory accesses.
Note that all valid entries in this table are odd values, which results from the fact that 2 words are allocated
for each long value in the modulo buffer.
For example, to create a circular buffer with four 32-bit locations, calculate M01 as follows:
The four 32-bit locations would require 8 words of data memory, so the M01 register is programmed with
the value “$0007.”
6-24
•
•
Modulo arithmetic is performed on word addresses.
M01 = 2 × (size of the buffer in long words) – 1
DSP56800E Core Reference Manual
M01
=
=
=
(
8 1
7
2 4
–
×
) 1
–
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