Epson S5U1C88348T, Manual

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4 CHANGING SETTINGS AND MOUNTING PARTS
II-8
EPSON
S5U1C88348T HARDWARE MANUAL
4.2 Replacing External RAM
When shipped from the factory, the S5U1C88348T has 32K bytes of RAM mounted in the IC socket on U6.
This RAM may be upgraded to 64K or 128K-byte RAM. RAM is mapped into the CE2 area (beginning
with address 100000h).
Check that the new RAM is mounted as shown in the following diagram.
28pin 32pin
Fig. 4.2.1 Installing RAM
When the above is complete, perform the following steps. (This work is required only when you use 64K-
byte RAM.)
(1) Cut the pattern connecting JP3 pins 1 and 2, then attach a jumper pin to JP3.
(2) Set up the JP3 jumper socket according to the size of the RAM.
Table 4.2.1 JP3 Settings
RAM size
32K bytes
64K bytes
128K bytes
JP3
1–2
1–2
2–3
4.3 Mounting External ROM
The S5U1C88348T may be used as the target board in ICE mode, or may be operated in MPU mode after
replacing its MPU board with another CPU (S1C88348/317/316/308). The S5U1C88348T provides a
pattern (U5) for mounting external ROM for such applications. To attach external ROM, solder a 32-pin
socket to this pattern.
You can use four ROM sizes: 32K bytes, 64K bytes, 128K bytes, and 256K bytes. ROM is mapped to the
CE0 area (beginning with address 0 for MPU mode or address 200000h for MCU mode). Check that the
ROM is mounted as shown in the following diagram.
28pin 32pin
Fig. 4.3.1 Installing ROM
Attach jumper pins to JP1 and JP2 and perform setup according to the ROM size used.
Table 4.3.1 JP1 and JP2 Settings
ROM size
32K bytes
64K bytes
128K bytes
256K bytes
JP1
1–2
2–3
1–2
2–3 JP2
1–2
1–2
Open
2–3