PPnet

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Network for PP-06 and PP01-16 computers

coaxial cable 75 Ohm, speed 500 kbit/s, max. length 1.5 km, Manchester coding, Token-bus (bus).

Card for connecting to the PPnet local network: SM 1270, 1274.

The card is internally designed so that the SRAM is on a bus that is accessible to both the Z80 and the host computer. At the same time, the driver reaches directly into RAM for results. The EPROM contains the code for the Z80 at addresses 0-10FF, from address 0x1200 to 0x1FFF is the BootROM code executed during POST, which is copied to the shared RAM when the Z80 firmware starts.

The firmware contains the string "D-XX, bison, orol, 28.2.1990", BootROM code then "D-XX, bison, a.dol.1989." and "LAN BOOT PROGRAM V.1.0 written by Anton Dolejsi, 1989"