ST18952 View Datasheet(PDF) - STMicroelectronics
Part Name
Description
MFG CO.
'ST18952' PDF : 67 Pages View PDF
ST18952
7.2 DMA registers
Address registers
Two 16-bit registers (unsigned) are dedicated per channel for address transfer:
• DIA: initial address. Contains the initial address of the selected address bus
(see DBC-bit of DGC register).
• DCA: current address. Contains the value to be transferred to the selected
address bus (see DBC-bit of DGC register) during the next transfer. The
different DCA values are:
Reset
DAI
1
X
0
0
0
1
0
1
0
1
DLA
X
X
0
1
1
DCC = 0
X
X
X
0
1
DCA(n+1)
0
DCA(n)
DCA(n) + 1
DCA(n) + 1
DIA
Note:
See ”DAIC: Address/interrupt control register” on page 24 for DAI and DLA definitions
Counting registers
Two 16-bit registers (unsigned) per channel are dedicated for count transfer.
For a transfer of an N data block, DIC and DCC registers have to be loaded with N-1.
When DCC content is 0 (valid transfer count), it is loaded with DIC content for the next transfer.
• DIC: initial count. Contains the total number of transfers of the entire block
• DCC: current count. Contains the remaining number of transfers required to fill
the entire block. It is decremented after each transfer. The DCC values are:
Reset
1
0
0
DCC = 0
X
0
1
DCA(n+1)
0
DCA(n) - 1
DIC
Control registers
Three 16-bit control registers are dedicated to the DMA controller interface. These are the
general control register, the address interrupt control register and the mask sensitivity control
register. They are detailed below.
23/66
Share Link: 
