Epson MFJ-1278B Benutzerhandbuch

The MFJ-1278B mother board has many jumper connectors.  Each jumper connector has a 
special function.  The Jumper Function chart, Table G-1 in this appendix, will help in 
identifying each jumper function. Figure G-1 will help in locating the jumper connectors 
easily. 
 
For normal operation a shorting jumper must be placed on the following connectors: JMP 5; 
JMP 8; JMP 9 pins 2,3; JMP 13; JMP 14 pins 1,2; JMP 16 pins 1,3 and pins 2,4; JMP 18 
pins 1,2; JMP 19 outside pair (one top,one bottom); JMP 22 pins 2,3; JMP 24 pins 1,2; JMP 
26 pins 1,,2; JMP E, F, G, H. Also on the mode disconnect header J4 the following pins need 
jumpers pins 1,2  11,12  13,14  17,18. 
 

Table G-1: Jumper Function 

JMP1 

Pin 1 & 2 

!DCD (RS-232C) stays on 

 

Pin 2 & 3 

!DCD (RS-232C) stays off 

 

OFF (Default) 

!DCD reflects connect status 

JMP2 

Pin 1 & 2 (Default) 

4.92 MHz CPU clock 

 

Pin 2 & 3 

2.46 MHz CPU clock 

JMP4 

ON 

Disable Tx watch-dog 

 

OFF (Default) 

Enable Tx watch-dog 

JMP5 

ON  (Default) 

Lithium battery connected 

 

OFF 

Lithium battery disconnected 

JMP7 

ON 

Analog loopback mode 

 

OFF (Default) 

Normal modem operation 

JMP8 

ON  (Default) 

Demodulator enabled 

 

OFF 

Demodulator calibrate 

JMP9 

Pin 1 & 2 

Calibrate U16 tones 

 

Pin 2 & 3 (Default) 

Normal modem operation 

JMP10 

ON 

Digital loopback mode 

 

OFF (Default) 

Normal modem operation 

JMP11 

LEFT 

Transmit data NRZ 

 

RIGHT (Default) 

Transmit data NRZI 

JMP13 

ON (Default) 

TTL, RTS enable 

 

OFF 

TTL, RTS disable  

JMP14 

Pin 1 & 2 (Default) 

FSK out normal 

 

Pin 2 & 3 

FSK out reverse 

JMP16 

Pin 1 & 2 

Without multi-gray levels