ADSP-BF537 Blackfin Processor Hardware Reference
5-101
Direct Memory Access
HMDMAx_BCINIT Registers
The handshake MDMA initial block count register (
HMDMAx_BCINIT)
,
shown in
, holds the number of transfers to do per edge of the
DMARx
control signal.
HMDMAx_BCOUNT Registers
The handshake MDMA current block count register (
HMDMAx_BCOUNT)
,
, holds the number of transfers remaining for the
current edge. MDMA requests are generated if this count is greater than 0.
Examples:
• 0000 = 0 transfers remaining
• FFFF = 65535 transfers remaining
The
BCOUNT
field is loaded with
BCINIT
when
ECOUNT
is greater than 0 and
BCOUNT
is expired (0). Also, if the
RBC
bit in the
HMDMAx_CONTROL
register is
written to a 1,
BCOUNT
is loaded with
BCINIT
. The
BCOUNT
field is decre-
mented with each MDMA grant. It is cleared when
HMDMA
is disabled.
Figure 5-20. Handshake MDMA Initial Block Count Registers
0
0
0
0
0
0
15 14
13 12
11 10
9
8
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
Handshake MDMA Initial Block Count Registers (HMDMAx_BCINIT)
BCINIT[15:0] (Initial Block
Count)
Reset = 0x0000
HMDMA0:
0xFFC0 3308
HMDMA1:
0xFFC0 3348
Summary of Contents for Blackfin ADSP-BF537
Page 42: ...Contents xlii ADSP BF537 Blackfin Processor Hardware Reference ...
Page 90: ...Development Tools 1 32 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 138: ...Programming Examples 4 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 340: ...SDC Programming Examples 6 84 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 606: ...Programming Examples 9 94 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 660: ...Programming Examples 10 54 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 720: ...Electrical Specifications 11 60 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 840: ...Programming Examples 13 42 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 876: ...Programming Examples 14 36 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 938: ...Programming Examples 15 62 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 958: ...Programming Examples 17 12 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 986: ...Programming Examples 18 28 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1162: ...G 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1218: ...Index I 56 ADSP BF537 Blackfin Processor Hardware Reference ...