Main Pba - Toshiba DP120F Service Manual

3. MAIN PBA

This section describes the functions of each circuit on the Main PBA.
The Main PBA is the main control center of this machine. With the CPU (IC66) as the central
component, it consists of the DMAC GA (IC16) for DMA transfer control, PTC GA (IC45) for
printer control, I/OP-1 GA (IC7) and I/OP-2 GA (IC48) for control of each I/O, Sub-CPU (IC37)
for control of low power consumption operation, and other peripheral devices.
CPU (IC66)
• Control of each GA
• Memory control
• Bus control
• Interrupt control
DMAC GA (IC16)
• DMA transfer control
• Memory control
• Control of communication circuits
• Interrupt control
• Generation of speaker clocks
• Watchdog timer function
PTC GA (IC45)
• DSC (Document Scan Control) control
• EET (Edge Enhancement Technology) control
• LSU control
• Fuser control
• Toner empty detection
• Drum unit and Developer assembly detection
• CODEC (MH, MR, MMR, JBIG) control
• TX motor control
• Top cover open detection
• Scanner cover open detection
• PC interface
• Generation of print clocks
DP120F/DP125F Circuit Description 7-26 March 2000 © TOSHIBA TEC