Transfer Count Control - Fujitsu FR60 Hardware Manual

16.3.7

Transfer Count Control

Specify the transfer count within the range of the maximum 16-bit length (1 to 65536).
Set the transfer count value in the transfer count register (DTC of DMACA).
■ Transfer Count Registers and Reload Operation
The register value is stored in the temporary storage buffer when the transfer starts and is decremented by
the transfer count counter. When the counter value becomes "0", transfer end for the specified count is
detected, and the transfer on the channel is stopped or waiting for a restart request starts (when reload is
specified).
[Features of the group of transfer count registers:]
• Each register has 16-bit length.
• All registers have a dedicated reload register.
• If transfer is activated when the register value is "0", transfer is performed 65536 times.
[Reload operation]
• The reload operation can be used only if reloading is enabled in a register that allows reloading.
• When transfer is activated, the initial value of the count register is saved in the reload register.
• If the transfer count counter counts down to "0", end of transfer is reported and the initial value is read
from the reload register and written to the count register.
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