Toshiba T-Series T4900CT, Manual

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T4900CT
The T4900CT system board shown in figure 1-3 is composed of the following major compo-
nents:
❑
A pentium processor, which incorporates a math co-processor and16 KB cache
memory.
❑
The following memory components:
Standard RAM: 8 MB, 64-bit data width (70 ns)
Cache memory: Total 16 KB (inside a Pentium)
System, Video, 128 KB (96 KB are used), 8-bit data width
BIOS: A 1-Mbit flash ROM is used (150 ns).
This ROM contains Initial Reliability Test (IRT), Basic
Input/Output System (BIOS), and video BIOS.
Video RAM: 1 MB, 16-bit data width.
Two 256Kx16 bit chips are used.
Memory card: 4, 8, 16, or 32 MB memory card can be installed.
32-bit data width.
❑
Super Integration (SI) T6W23, which stores the following components:
• Two Direct Memory Access Controllers (DMAC): 82C37
• Two Programmable Interrupt Controllers (PIC): 82C59
• One Programmable Interval Timer (PIT): 82C54
• One Floppy Disk Controller (FDC): TC8565
• One Serial Input/Output Controller (SIO): 16550
• One Variable Frequency Oscillator (VFO): TC8568
• One I/O Controller
• One Printer Port Controller
• One Speaker Controller
❑
A Real Time Clock (RTC)
One T9934 chip is used. The T9934 has 128 bytes of memory. Fourteen bytes of
memory are used for the calendar and clock. The remaining 114 bytes are used for the
system configuration data.
❑
A Keyboard Controller (KBC)
One M37452M4 chip is used. This KBC includes the keyboard scan controller and
keyboard interface controller. The KBC controls the internal keyboard, external
keyboard port, PS/2 mouse port, and pointing stick.
❑
VGA display controller: F65545 (208-pin)
3.3 volt operation. This controller controls internal and external VGA compatible
display and external SVGA compatible display with Analog Digital Converter (DAC).
It can display data on the internal and external display at the same time.