Fujitsu F2MC-16L Series User Manual page 14

The two LED Display Registers (7000Ch and 7000Dh) are two write-only register for
controlling the LED Displays. The high byte controls the left LED Display and the low byte the
right one. The different bits are assigned to the LED-segments as follows:
15 14 13
P1 G1 F1
Note, that any segment is lighted up if the appropriate bit is set to "0" (inverse logic). E.g.
"A2" is coded as (7000Ch)=88A4h and "HI" is coded as (7000Ch)=89F9h.
The "Hardware Standby" pull-up switch (SW3/1) in default position connects HST to a pull-
up resistor for normal operation. This switch can normally be kept in this position even if the
HST -pin of JP39 is used. As the RST -signal of JP42 is only a probe signal, HST can be used
for an external reset circuit. (Note, the differences between RST and HST might be found in
the MB90670/675 user manual.)
The Mode Pin 1 Switch (SW3/2) sets the MD1-pin. SW3/2 in position "On" enables reading
reset vector from external bus (default). Otherwise the vector is read from internal (on-chip)
ROM.
MD0 is hard wired with "1" and MD2 is hardwired with "0". This configuration allows 16 Bit
busses only . EPROM-write mode is not possible.
The Terminal Reset Jumper (JP14) connects the DTR-line of the external RS232 port to a
special reset circuit. Leave it out, if this option is not requested or the terminal causes
misoperation.
The Voltage Selector Jumper (JP18) reduces the whole board power supply voltage to a value
suitable for most 3V and 3.3V circuits. It is intended for further modifications using 3V-
devices. If disabled (default) the voltage is set to 5V.
The A/D-Reference Jumpers (JP21..24) are intended for configuring the external A/D circuit
for test purpose. JP23 connects AVr − -pin to AVSS -pin and JP24 connects AVr + -pin to
AVCC -pin. JP21 connects the AVSS to GND . AVr − is connected to GND too, if both
JP21 and JP23 are enabled. JP22 connects the AVCC to VCC . AVr + is connected to VCC
too, if both JP22 and JP24 are enabled. Disable these jumpers, if the appropriate pin of JP39 is
used.
The Terminal Break Jumper (JP37) enables the external UART chip set to generate a hardware
interrupt. So the user can break the program by pressing any key of the (master) terminal
keyboard. This option occupies hardware interrupt #3 of the microcontroller. Remove the
jumper, if this interrupt resource is needed. Removing the jumper in order to disable the
keyboard break function is not necessary, because the monitor provides a special command
(UBREAK).
The Monitor Reset Button activates the Monitor Reset. The Monitor Mode register and User
Mode register are cleared, i.e. all user mapping modes are disabled.
The User Reset Button activates the User Reset. If the Monitor Mode register is set to 1, the
User Mode register value depends on SW3/3 position (on - User Mode 0, off - User Mode 1).
The reset vector is read from RAM 3 (User Mode 0 and User Mode 1 sub-mode "a") or from
Module 1 (User Mode 1 sub-mode "b" - SW3/3 and SW3/4 off).
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FUJITSU MB90675-Evaluation Board - User Manual
12 11 10 9 8
E1 D1 C1 B1 A1
7 6 5 4 3
P0 G0 F0 E0 D0
© FUJITSU Mikroelektronik GmbH 1996
2 1 0
C0 B0 A0