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Texas Instruments PS-6860Si

Date of introduction:  1996 Display technology:  LCD dot matrix
New price:   Display size:  6 lines by 24 char
Size:  3.3" x 5.1" x 0.70"
 85 x 129 x 18 mm3
   
Weight:  4.6 ounces, 130 grams Serial No:  
Batteries:  2*CR2032 Date of manufacture:  year 1996
AC-Adapter:   Origin of manufacture:  Taiwan (C)
Precision:  12 Integrated circuits:  CPU: Toshiba T6M88
 ROM: Macronix MX27C512
 RAM: Samsung KM681000
 Display: 2*LCD-Driver
Memories:  128kB RAM    
Program steps:   Courtesy of:  Joerg Woerner

The PS-6860Si replaced the earlier PS-6800 within one year. The changes are minor:

he PS-6155 Dock-station cradle to synchronize data with 
    the Lotus Organizer 97 software was optimzed.
The display of the organizer supporting 6 lines by 24 characters was 
    enhanced with a greenish backlite feature called Indiglo.

Dismantling this PS-6860Si manufactured early in 1996 by Compal Electronics in Taiwan reveals no surprises. The printed circuit board (PCB) looks very familiar to us and we identify the major components immediately.

The hardware resembles more or less its predecessor PS-6800 but is centered around a Toshiba T6M88 Application Specific CPU based on the 8-bit Z80 core instead the previous T6M76.

The pictured PS-6860Si uses a Macronix MX27C512 program memory, an OTP-ROM with a capacity of 64k Bytes. Later products use a chip marked with AB23512.

The data memory of the PS-6760Si, PS-6860Si and PS-6960Si are specified with 64k Bytes, 128k Bytes resp. 256k Bytes - the layout of the printed circuit board (PCB) suggests immediately the technical solution: The PCB accommodates one or two different sized memory chips in a very flexible configuration, this PS-6860Si hosts one Samsung KM681000 chip sporting a capacity of 128k Bytes.

The PS-6860Si uses two driver chips in Chip-on-Board (COB) technolgy on the Main-PCB, we couldn't identify the manufacturer and type of them.

 

 

 

It took another year until the PocketMate 300 appeared with a better keyboard layout.

 

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If you have additions to the above article please email: joerg@datamath.org.

Joerg Woerner, June 25, 2002. No reprints without written permission.