Cpu - Sony UP-D2550S Service Manual

4-1-4. CPU

IC204 is a system controller CPU and its main functions are as follows.
1) Communication with the host computer
2) Serial-communication (Pins 77 through 80) with the mechanical control CPU (PRT-11 board)
3) Sets data in the memory control gate array (IC102)
4) Sets data in the color palette IC101
5) Serial-communication with the EEPROM (IC201)
6) Lights up LEDs
Print, Alarm, Ribbon, Paper
7) Determines key inputs
Print, Stop
8) Sounds the buzzer
9) Selects the marking
The program is memorized in the external ROM IC210.
CNI212 is a socket for tools. It is used for inserting the LED display for showing data during
adjustments.
S201 through S207 are also keys for adjustments.
Address map
0000H — DFFFH Program territory IC210
D000H — D7FFH LED display IC IC212 (Writing only)
D800H — DFFFH DRAM writing IC102 (Writing only)
E000H — E7FFH Color adjust IC
E800H — EFFFH SCSI protocol controller IC209
F000H — F77FH Memory control IC102
F780H — FB7FH Reserve
FB80H — FF7FH CPU bult-in RAM
FF80H — FF87H Unused
FF88H — FFFFH CPU I/O
UP-D2550S (UC,CE) 4-3