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Sharp Pocket Computer Resources
Sharp Pocket Computer PC-1280 Resources

Sharp Pocket Computer PC-1280 Resource Page

Documentation

For manuals and documentation related to Sharp pocket computers in general have a look at the Documentation Section.

System Addresses

Address Description
&FDCD,&FDCE The RESTORE pointer. It is possible to remember the RESTORE pointer with e.g. B=256* PEEK &FDCE+ PEEK &FDCD and go to the remembered position with POKE &FDCD,B-256* INT (B/256), INT (B/256)

Accessing the display

The 1280 has a GPRINT-command, which you can use from BASIC. If you want to access the display from a machine language program, port a program from other models (witch draw graphics with POKE) or just access the special function display, then read on:

POKE &283C,X
1 BATT
2 -
4 -
8 RSV
16 PRO
32 RUN
64 CAL
128 -
POKE &283D,X
1 -
2 DEF
4 SHIFT
8 DBL
16 -
32 -
64 -
128 -
POKE &287C,X
1 E
2 M
4 RAD
8 G
16 -
32 -
64 PRINT
128 -
POKE &287D,X
1 jap. 1)
2 jap. 2)
4 SML
8 DE
16 -
32 -
64 -
128 -

1) Japanese character, looks like 'Pi'-'Tau'
2) Japanese character, looks like '+'

Note, that I wasn't able to locate the busy-flag, because this is reseted by the sharp operating system after performing the POKE. The flag may be located with a little machine language program, but this wasn't important enough for me to implement it. If you have done it, just mail me your result ...

Remember, that switching the display may activate the corresponding mode e.g. switching "SHIFT" on will cause the next key you press to activate the orange-coloured symbol.

To access the display blocks just write to the display memory: POKE Addr,Pattern

The display columns have addresses as shown in the table below:

Characters pos. 0-11,0 Characters pos. 12-23,0
&2800 &283B &2A00 &2A3B
Characters pos. 0-11,1 Characters pos. 12-23,1
&2840 &287B &2A40 &2A7B

As you can see, the display is divided into four block, all addressed bottom up.

Calculating the column pattern:
 

The pattern is calculated by adding the value of every pixel you want to display in black together, e.g. the second column in the picture at the right side would be 4+32+64=100. If you want to display the figure at the right side at character position 0, you would use

POKE &2800,2,100,29,100,2

If you want to display the figure at the right side at character position 9, you would use

POKE &282D,2,100,29,100,2

1
2
4
8
16
32
64

If you want to keep the display stable for a while, just insert a waiting loop:

FOR I=0 TO 200:NEXT I

Unlike most of the Sharp pocket computers, the PC-1280 has no nasty side effects at the right side of the display while doing direct access to the display memory. With this model it is not necessary to turn the display on with a CALL, because it is not turned off during calculations.

Here's an example which fills the display from the left to the right with black columns, first the upper line, then the lower line:


20 FOR I=0 TO &3B
30 POKE &2800+I,&FF
40 NEXT I
50 FOR I=&7B TO &40 STEP -1
60 POKE &2A00+I,&FF
70 NEXT I
80 FOR I=0 TO &3B
90 POKE &2840+I,&FF
100 NEXT I
110 FOR I=&7B TO &40 STEP -1
120 POKE &2A40+I,&FF
130 NEXT I

Programs

Have a look at the PC-1280 File Archive. To avoid minikeyboard typing, first have a look at Tools to link your pocket computer to your big PC.

Edgar Pühringer
last modified: 2009-10-14