412
SAM4CP [DATASHEET]
43051E–ATPL–08/14
26.9.1 Bus Matrix Master Configuration Registers
Name:
MATRIX_MCFGx [x=0..6]
Address:
0x400E0200 (0), 0x48010000 (1)
Access:
Read/Write
This register can only be written if the WPEN bit is cleared in the
“Write Protection Mode Register”
.
ULBT: Undefined Length Burst Type
0: Unlimited Length Burst
No predicted end of burst is generated, therefore INCR bursts coming from this master can only be broken if the Slave Slot Cycle
Limit is reached. If the Slot Cycle Limit is not reached, the burst is normally completed by the master, at the latest, on the next
AHB 1 Kbyte address boundary, allowing up to 256-beat word bursts or 128-beat double-word bursts.
This value should not be used in the very particular case of a master capable of performing back-to-back undefined length bursts
on a single slave, since this could indefinitely freeze the slave arbitration and thus prevent another master from accessing this
slave.
1: Single Access
The undefined length burst is treated as a succession of single accesses, allowing re-arbitration at each beat of the INCR burst or
bursts sequence.
2: 4-beat Burst
The undefined length burst or bursts sequence is split into 4-beat bursts or less, allowing re-arbitration every 4 beats.
3: 8-beat Burst
The undefined length burst or bursts sequence is split into 8-beat bursts or less, allowing re-arbitration every 8 beats.
4: 16-beat Burst
The undefined length burst or bursts sequence is split into 16-beat bursts or less, allowing re-arbitration every 16 beats.
5: 32-beat Burst
The undefined length burst or bursts sequence is split into 32-beat bursts or less, allowing re-arbitration every 32 beats.
6: 64-beat Burst
The undefined length burst or bursts sequence is split into 64-beat bursts or less, allowing re-arbitration every 64 beats.
7: 128-beat Burst
The undefined length burst or bursts sequence is split into 128-beat bursts or less, allowing re-arbitration every 128 beats.
Unless duly needed, the ULBT should be left at its default 0 value for power saving.
31
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30
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29
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28
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27
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26
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25
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24
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23
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22
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21
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20
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19
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18
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17
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16
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15
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14
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13
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12
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11
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10
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9
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8
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7
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6
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5
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4
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3
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2
1
0
ULBT