Altera Cyclone V Device Handbook page 831

cv_54016
2013.12.30
where:
[S] If S is present and the loop starts with DMALP, then the assembler sets bs to 0 and x to 1. The instruction
is conditional on the state of the request_type flag:
• request_type = Single
• The DMAC executes the DMALPEND
• request_type = Burst
• The DMAC performs a DMANOP and therefore exits the loop.
[B] If B is present and the loop starts with DMALP, then the assembler sets bs to 1 and x to 1. The
instruction is conditional on the state of the request_type flag:
• request_type = Single
• The DMAC performs a DMANOP and therefore exits the loop.
• request_type = Burst
• The DMAC executes the DMALPEND
If you do not specify the S or B operand, the assembler sets bs to 0 and x to 0, and the DMAC always executes
the DMALPEND.
Note:
You must not specify the S or B operand when a loop starts with DMALPFE. If you do, the assembler
issues a warning message and sets bs to 0, x to 0, and nf to 1. In the same way as for DMALPFE, the
DMAC uses the state of the request_last flag to control when it exits the loop.
Note: The DMAC sets the value of the:
• request_type flag when it executes a DMAWFP instruction.
• request_last flag to 1 when the corresponding peripheral issues the last request command through
the peripheral request interface.
To correctly assign the additional bits in the DMALPEND instruction, the assembler determines the values
for:
backwards_jump[7:0] Sets the relative location of the first instruction in the program loop. The
assembler calculates the value for backwards_jump[7:0] by subtracting the address of the first
instruction in the loop from the address of the DMALPEND.
• nf sets it to:
• 0 if DMALPFE started the program loop
• 1 if DMALP started the program loop.
• lc sets it to:
• 0 if the loop counter 0 registers contains the loop counter value
• 1 if the loop counter 1 registers contains the loop counter value
• 1 if DMALPFE started the program loop.
Operation
DMA Controller
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DMALPEND[S | B]
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