M306N5FCTFP Renesas Electronics America, M306N5FCTFP Datasheet - Page 117

• Manufacturer Part Number: M306N5FCTFP
• Description: IC M16C MCU FLASH 100QFP
• Manufacturer: Renesas Electronics America
• Series: M16C™ M16C/6Nr

Specifications of M306N5FCTFP

• Core Processor: M16C/60
• Core Size: 16-Bit
• Speed: 20MHz
• Connectivity: CAN, I²C, IEBus, SIO, UART/USART
• Peripherals: DMA, WDT
• Number Of I /o: 87
• Program Memory Size: 128KB (128K x 8)
• Program Memory Type: FLASH
• Ram Size: 5K x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 26x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 100-QFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

M16C/6N Group (M16C/6N5)
Rev.2.40
REJ09B0011-0240
12.1 Transfer Cycle
The transfer cycle consists of a memory or SFR read (source read) bus cycle and a write (destination write)
bus cycle. The number of read and write bus cycles is affected by the source and destination addresses of
transfer. During memory expansion and microprocessor modes, it is also affected by the BYTE pin level.
Furthermore, the bus cycle itself is extended by a software wait or RDY signal.
12.1.1 Effect of Source and Destination Addresses
12.1.2 Effect of BYTE Pin Level
12.1.3 Effect of Software Wait
12.1.4 Effect of RDY Signal
Figure 12.5 shows the Transfer Cycles for Source Read. For convenience, the destination write cycle is
shown as one cycle and the source read cycles for the different conditions are shown. In reality, the
destination write cycle is subject to the same conditions as the source read cycle, with the transfer cycle
changing accordingly. When calculating transfer cycles, take into consideration each condition for the
source read and the destination write cycle, respectively. For example, when data is transferred in 16-bit
unit using an 8-bit bus ((2) on Figure 12.5), two source read bus cycles and two destination write bus cycles
are required.
If the transfer unit and data bus both are 16 bits and the source address of transfer begins with an odd
address, the source read cycle consists of one more bus cycle than when the source address of transfer
begins with an even address.
Similarly, if the transfer unit and data bus both are 16 bits and the destination address of transfer begins
with an odd address, the destination write cycle consists of one more bus cycle than when the destination
address of transfer begins with an even address.
During memory expansion and microprocessor modes, if 16 bits of data are to be transferred on an 8-bit
data bus (input on the BYTE pin = high), the operation is accomplished by transferring 8 bits of data twice.
Therefore, this operation requires two bus cycles to read data and two bus cycles to write data.
Furthermore, if the DMAC is to access the internal area (internal ROM, internal RAM, or SFR), unlike in
the case of the CPU, the DMAC does it through the data bus width selected by the BYTE pin.
For memory or SFR accesses in which one or more software wait states are inserted, the number of bus
cycles required for that access increases by an amount equal to software wait states.
During memory expansion and microprocessor modes, DMA transfers to and from an external area are
affected by the RDY signal. Refer to 7.2.6 RDY Signal.
Apr 14, 2006
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12. DMAC