AMD SD188EM, User Manual

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SD188ES/SD188EM Demonstration Board User’s Manual 2-2
1.1
Layout and Placement
The design of the SD188ES/SD188EM demonstration board emphasizes ease of
use and small size. Refer to Figure 2-1 on page 2-3 for board layout and component
placement.
The SD188ES/SD188EM demonstration board has the Flash and SRAM memory
devices (U4 and U3) directly below the processor. This placement keeps the
memory devices as close as possible to the processor to minimize noise and trace
reflections. The 40-MHz fundamental mode crystal (Y1) is located to the right of
the processor. The expansion interface (J2 and J3) is located at the bottom of the
board for easy connection and access. Finally, the 5.5-mm power-supply barrel
connector (J1) is positioned in the upper, left corner of the board.
The RS-232 serial interfaces are positioned on the right of the board. Please note
that the ES version of the board features two serial ports (P0 and P1), which are
driven by the two asynchronous serial interfaces on the Am188ES microcontroller.
The Am188EM microcontroller provides one asynchronous serial interface so the
EM version of the board implements the serial port with a DB-9 connector (P1).
Table 2-1. SD188ES/SD188EM Demonstration Board Parts List
Part
Number Description For more
information, see
CR1–CR10 Power and signal LEDs Page 2-13
J1 Power connector Page 2-14
J2-J3 Expansion interface Page 2-10
U1 Voltage supply supervisor (TI TL7705A) Page 2-10
U2 Am188ES or Am188EM 40-MHz
microcontroller Page 2-4
U3 Flash memory Page 2-7
U4 SRAM Page 2-7
U5–U6 RS-232 driver/receiver devices (MAX232) Page 2-8
Y1 40-MHz fundamental mode crystal Page 2-10
frtbook : newch2 Page 2 Monday, June 2, 1997 3:37 PM