Renesas RL78 Series User Manual page 661

RL78/G1D
The RL78/G1D has an internal DMA (Direct Memory Access) controller.
Data can be automatically transferred between the peripheral hardware supporting DMA, SFRs, and internal RAM
without via CPU.
As a result, the normal internal operation of the CPU and data transfer can be executed in parallel with transfer
between the SFR and internal RAM, and therefore, a large capacity of data can be processed. In addition, real-time
control using communication, timer, and A/D can also be realized.
17.1 Functions of DMA Controller
Ο Number of DMA channels: 4 channels
Ο Transfer unit: 8 or 16 bits
Ο Maximum transfer unit: 1024 times
Ο Transfer type: 2-cycle transfer (One transfer is processed in 2 clocks and the CPU stops during that
processing.)
Ο Transfer mode: Single-transfer mode
Ο Transfer request: Selectable from the following peripheral hardware interrupts
● A/D converter
● Serial interface
(CSI00, CSI20, CSI21, UART0, and UART1)
● Timer (channel 0, 1, 2, or 3)
Ο Transfer target: Between SFR and internal RAM
Here are examples of functions using DMA.
● Successive transfer of serial interface
● Consecutive capturing of A/D conversion results
● Capturing A/D conversion result at fixed interval
● Capturing port value at fixed interval
R01UH0515EJ0120 Rev.1.20
Dec 16, 2016
CHAPTER 17 DMA CONTROLLER
CHAPTER 17 DMA CONTROLLER
640