Toshiba T-Series T4500, User Manual

Page: 7 / 212

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❑
Clock Generator receives 14.31818 MHz (X1) and generates the following frequencies:
●
20 MHz for the CPU
●
14.7456 MHz for the COM
●
24 MHz for the FDC and VFO
●
16 MHz is used for GA
●
14.31818 MHz for WD90C26A (for VGA)
OSC (X3) generates 32.768 KHz for RTC.
❑
Gate Array
System Controller Gate Array
This gate array has the following functions:
●
Memory Controller
-
DRAM Controller
- CPU Controller
- Compatible Bus Interface Controller
●
Bus Controller
-
Compatible Bus Interface Controller
- Compatible Access Controller
- DMAC Controller
- I/O Controller
●
Address Latch Controller
-
32-Bit
→
16-Bit Controller
- Address Latch
- DMA Address Generator
- Refresh Address Generator
●
I/O Register
-
Compatible I/O Port
- Saving the data of the Register (in resume) Controller
- Toshiba Special Register
●
20 MHz/10 MHz Controller
-
Data Bus Change Controller
- Data Latch
Sub LCD Controller Gate Array
This gate array has the following functions:
●
Status Indicator Panel Controller
-
LCD Segment Flashing Controller
●
Internal Communication Controller
-
KBC/Power Supply Micro Processor/Main CPU Communication
Controller
- KBC/Power Supply Micro Processor Interrupt Controller