M16C Datasheet, PDF (78/262 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

DMAC
Preliminary Specifications REV.B
Mitsubishi microcomputers
Specifications in this manual are tentative and subject to change.
M16C / 6N Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
(2) DMAC transfer cycles
Any combination of even or odd transfer read and write addresses is possible. Table 7-2 shows the
number of DMAC transfer cycles.
The number of DMAC transfer cycles can be calculated as follows:
No. of transfer cycles per transfer unit = No. of read cycles x j + No. of write cycles x k
Table 7-2. No. of DMAC transfer cycles
Transfer unit
8-bit transfers
(DMBIT= “1”)
16-bit transfers
(DMBIT= “0”)
Bus width
16-bit
(BYTE= “L”)
8-bit
(BYTE = “H”)
16-bit
(BYTE = “L”)
8-bit
(BYTE = “H”)
Access address
Even
Odd
Even
Odd
Even
Odd
Even
Odd
Single-chip mode Memory expansion mode
Microprocessor mode
No. of read No. of write No. of read No. of write
cycles
cycles
cycles
cycles
1
1
1
1
1
1
1
1
—
—
1
1
—
—
1
1
1
1
1
1
2
2
2
2
—
—
2
2
—
—
2
2
Coefficient j, k
Internal memory
Internal ROM/RAM Internal ROM/RAM SFR area
No wait
With wait
1
2
2
External memory
Separate bus Separate bus
No wait
With wait
1
2
Multiplex
bus
3
78