Figure 1-12. C060 Main, C061 Main, And C060 Main B Boards; C060 Main, C061 Main, And C060 Main B Board (Main Control Circuit Board) - Epson LQ-870 Service Manual

1.7.1 C060 MAIN, C061 MAIN, and C060 MAIN B Boards (Main Control Circuit Board)
The CO60 MAIN board was the original board used in the LQ-870/1170 printer when it was released in 1991. (There
were separate CO60 MAIN boards for the LQ-870 and LQ-1170, and it required a driver board.) The CO61 board for the
LQ-1170, which became available in 1992, combined the main board with the driver circuitry. There are now two new
CO60 MAIN B boards, which also contain driver circuitry, and are defined at the factory for use with either the LQ-870
or the LQ-1170.
All these boards contain a TMP90CO4 8-bit CPU, an EO5A49BB gate array, a PROM (512K), a PSRAM (256K), a mask
ROM (1 M), and an EEPROM. In addition, the CO61 and CO60 MAIN B also include the components and circuits built
into the CO60 DRV board. The CO60 MAIN B board for the LQ-1170 contains an SRAM in location 5A, which is not
mounted in the CO60 MAIN B board for the LQ-870.
EEP

Figure 1-12. C060 MAIN, C061 MAIN, and C060 MAIN B Boards

CPU TMPSOC 04 1N (2C)
I
MASK ROM
M65256 (4A)
CPU
(CO60 MAIN-B)
Driver Circuit (Same as CO60 DRV)
MASK ROM (2A)
Driver circuit
PROM (3A)
MASK ROM (WA)
1-27
PSRAM