YouTube

 

ppc2ppc4Model: Portable Professional Computer (PPC)  Color Version   
Adapter: 110 volt
Year: 1983
Keyboard: QWERTY full-stroke keyboard with arrow keys and separated numeric keypad
Cpu: Intel 8086 Speed: 5 mhz CO-processor: 8087
Ram: 64k (up to 768k) Sound: Beeper
Text mode: 80 x 25 Graphics mode: 720 x 300 
Size - Weight: 47 x 42 x 19 cm / 12 kg with the monochrom monitor / 14 kg with the color monitor
I/O ports: Parallel/Centronics port, 5 expansion slots (non IBM compatible), 4 x serial ports
Media: two 5''1/4 disk-drive (320k)
OS: MS-DOS 2.1 CP/M 86, UCSD P-system, Prologue and Concurrent CP/M 86.
Peripherals: 10Mb or 20Mb hard-drive ( need interface), RAM expansion cards, Voice recognition card, Ethernet card.
Price: 64k model about 3000$ (USA, november 1983) / 64k model : £ 4.000.000  (Italy, 1985)

 

 

WIkipedia TIPC


TroubleShooting

 Video Tests

 ppc3ppc1Here you can see some video card tests.

 

 

 


 Here we tell you about some necessary repairs after the mother board broke, during the 2nd edition dedicated to Texas Instruments in the city of Rieti in 2023.

Mother Board broke

led mb

mother boardThe first thing to do in the event of a fault is to check the status of the three LEDs above the mother board CR1, CR2, CR3. Normal operation at boot is the switching on of all three and subsequently the switching on of the red, orange and solid green. In our case all three are turned on, the manual states that there is a block in reading the EPROMs.

  

 u61 schemeWe started investigating both with the oscilloscope and with a logic analyzer, we concentrated on reading the data and in particular on U61.

 

 

 

u61 guastologic analyzeru61 02We noticed that on the EPROM side and on the U61 (74LS245) bus transceiver side, the data was not moving. After replacement, the mother board works again