m37702s1afp Mitsumi Electronics, Corp., m37702s1afp Datasheet - Page 35

• Manufacturer Part Number: m37702s1afp
• Description: Single-chip 16-bit Cmos Microcomputer
• Manufacturer: Mitsumi Electronics, Corp.

(1) One-shot mode [00]
The A-D conversion pins are selected with the bit 0 to 2 of A-D
control register. A-D conversion can be started by a software trig-
ger or by an external trigger.
A software trigger is selected when the bit 5 of A-D control register
is “0” and an external trigger is selected when it is “1”.
When a software trigger is selected, A-D conversion is started
when bit 6 (A-D conversion start flag) is set. A-D conversion ends
after 57
conversion interrupt control register. At the same time, A-D control
register bit 6 (A-D conversion start flag) is cleared and A-D con-
version stops. The result of A-D conversion is stored in the A-D
register corresponding to the selected pin.
If an external trigger is selected, A-D conversion starts when the
A-D conversion start flag is “1” and the AD
“H” to “L”. In this case, the pins that can be used for A-D conver-
sion are AN
analog voltage input pin AN
software trigger except that the A-D conversion start flag is not
cleared after A-D conversion and a retrigger can be available dur-
ing A-D conversion.
(2) Repeat mode [01]
The operation of this mode is the same as the operation of one-
shot mode except that when A-D conversion of the selected pin is
complete and the result is stored in the A-D register, conversion
does not stop, but is repeated. Also, no interrupt request is issued
in this mode. Furthermore, if software trigger is selected, the A-D
conversion start flag is not cleared. The contents of the A-D regis-
ter can be read at any time.
(3) Single sweep mode [10]
In the sweep mode, the number of analog input pins to be swept
can be selected. Analog input pins are selected by bits 1 and 0 of
the A-D sweep pin selection register (1F
ure 45. Two pins, four pins, six pins, or eight pins can be selected
as analog input pins, depending on the contents of these bits.
A-D conversion is performed only for selected input pins. After
A-D conversion is performed for input of AN
result is stored in A-D register 0, and in the same way, A-D conver-
sion is performed for selected pins one after another. After A-D
conversion is performed for all selected pins, the sweep is
stopped.
A-D conversion can be started with a software trigger or with an
external trigger input. A software trigger is selected when bit 5 is
“0” and an external trigger is selected when it is “1”.
When a software trigger is selected, A-D conversion is started
when A-D control register bit 6 (A-D conversion start flag) is set.
When A-D conversion of all selected pins end, an interrupt request
bit is set in the A-D conversion interrupt control register. At the
same time, A-D control register bit 6 (A-D conversion start flag) is
cleared and A-D conversion stops.
When an external trigger is selected, A-D conversion starts when
the A-D conversion start flag is “1” and the AD
from “H” to “L”. In this case, the A-D conversion result of the trig-
ger input itself is stored in the A-D register 7 because the AD
pin is shared with AN
AD
0
cycles and an interrupt request bit is set in the A-D
to AN
6
7
because the AD
pin.
7
. The operation is the same as with
______
TRG
______
16
TRG
address) shown in Fig-
pin is shared with the
______
0
pin, the conversion
input changes from
TRG
input changes
M37702M2AXXXFP, M37702M2BXXXFP
______
TRG
The operation is the same as done by software trigger except that
the A-D conversion start flag is not cleared after A-D conversion
and a retrigger can be available during A-D conversion.
(4) Repeat sweep mode [11]
The difference with the single sweep mode is that A-D conversion
does not stop after converting from the AN
pins, but repeats again from the AN
among the selected pins. Also, no interrupt request is generated.
Furthermore, if software trigger is selected, the A-D conversion
start flag is not cleared. The A-D register can be read at any time.
Fig. 45 A-D sweep pin selection register configuration
M37702S1AFP, M37702S1BFP
7
6
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
5
4
3
MITSUBISHI MICROCOMPUTERS
2
1
0
0
A-D sweep pin
selection register
pin. The repeat is performed
0 0 : AN
0 1 : AN
1 0 : AN
1 1 : AN
0
pin to the selected
0
0
0
0
, AN
to AN
to AN
to AN
1
(2 pins)
3
5
7
Address
(4 pins)
(6 pins)
(8 pins)
1F
16
35