M38197MA Datasheet, PDF (35/60 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER

MITSUBISHI MICROCOMPUTERS
3819 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
q FLD Automatic Display RAM
The FLD automatic display RAM area is the 96 bytes from ad-
dresses 0F8016 to 0FDF16. The FLD automatic display RAM
area can store 6-byte segment data up to 16 digits (maximum).
Addresses 0F8016 to 0F8F16 are used for PA segment data,
addresses 0F9016 to 0F9F16 are used for P8 segment data,
addresses 0FA016 to 0FAF16 are used for P9 segment data,
addresses 0FB016 to 0FBF16 are used for P3 segment data,
addresses 0FC016 to 0FCF16 are used for P0 segment data,
and addresses 0FD0 to 0FDF16 are used for P1 segment data.
FLD Data Pointer and FLD Data Pointer
Reload Register
(FLDDP) 003816
Both the FLD data pointer and FLD data pointer reload register
are 7-bit registers allocated at address 003816. When writing data
to this address, the data is written to the FLD data pointer reload
register, when reading data from this address, the value in the
FLD data pointer is read.
The FLD data pointer indicates the data address in the FLD auto-
matic display RAM to be transferred to a segment. The FLD data
pointer reload register indicates the first digit address of the most
significant segment.
The value which adds 0F8016 to these data is actual address in
memory.
The contents of the FLD data pointer indicate the first address of
segment P1(the contents of the FLD data pointer reload register)
at the start of automatic display. The FLDC data pointer content
changes repeatedly as follows: when transferring the segment P1
data to the segment, the content decreases by –16; when transfer-
ring the segment P0 data, it decreases by –16; when transferring
the segment P3 data, it decreases by –16; when transferring the
segment P9 data, it decreases by –16; when transferring the seg-
ment P8 data, it decreases by –16; when transferring the segment
PA data, it increases by +79. Once it reaches “00”, at the next tim-
ing the value in the FLD data pointer reload register is transferred
to the FLD data pointer. In this way, the 6-byte data of P1, P0, P3,
P9, P8 and PA segments for 1 digit are transferred.
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