4 bit microcontroller for single-chip digital tuning systems.
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230 MHz)
Features built-in 1/4-duty, 1/2-bias LCD drivers and a built-in 3 V booster circuit for the display.
Data memory (RAM) and ports are easily backed up.
Program memory (ROM): 16 bit 脳 7168 steps
Data memory (RAM): 4 bit 脳 256 words
62-instruction set (all one-word instructions)
Instruction execution time: 40 碌s (with 75-kHz crystal) (MVGS, DAL instructions: 80 碌s)
Many addition and subtraction instructions (12 types each addition and subtraction)
Powerful composite decision instructions (TMTR, TMFR, TMT, TMF, TMTN, TMFN)
Data can be transmitted between addresses on the same row.
Register indirect transfer available (MVGD, MVGS instructions).
16 powerful general registers (located in RAM)
Stack levels: 2
Free branching (JUMP instructions) is allowed in the 7168 steps of program memory (ROM) as there are no
pages or fields.
16 bits of any address in the 1024 program memory steps (ROM) can be referenced (DAL instructions).
Features independent frequency input pins (FM
IN
and AM
IN
) and two (DO1 and DO2) phase comparator
outputs for FM/VHF and AM.
Seven kinds of reference frequencies can be selected via software.
Powerful input/output instructions (IN1 to 3, OUT1 to 3).
Dedicated input ports (K0 to K3) for key input, 29 LCD drive pins (100 segments maximum) available.
29 I/O ports: 27 input/output programmable in 1-bit units, 1 output-only port, and 1 input-only port. The 2 IF
IN
,
and DO1 pins can be switched by instruction to IN1 (input-only) or OT2 (output-only). In addition, 9 output
LCD output pins for S17 to S25 can be switched to I/O port in 1-bit units.
Three backup modes available by instruction: Only CPU operation, crystal oscillation only, clock stop.
Features a built-in 2-Hz timer F/F and a built-in 10/100 Hz interval pulse outputs (internal port for time base).