FT757GX CPU Project


Before you attempt this you should check for a ~60Hz pulse onPB2. This is pin 3 of the display connector (or pin 14 of the cpu ). Ifthis is missing it will stop the original Yaesu cpu from working. The cause of the missingPB2 signal is a faulty display CPU, not the main CPU.

I stopped development on this project a long time ago. Having said that the code works and is here for anyone who might need it.

After buying a FT757GX with a faulty cpu cheap i discovered that theyare no longer available from Yaesu, and i couldnt track one downanywhere. With no other option i decided that i would jump in headfirst, buy a PIC and program up my own cpu!! So i purchased a PIC18F452($11.84 from http://www.futurlec.com.au) and set off to find a free language i could program in, i found the JAL Compiler combined that with JALEdit for an ide i was on my way.

Almost all features of the original cpu are implemented. Only coderelating to the transmit inhibit and CAT needs to be added.Not all the functions are as per original Yaesu cpu but they are veryvery close. There are still issues with smooth operation of the vfoknob, it sometimes misses a count pulse while updating the display. Imight fix this one day by making it interupt driven.

The current release is Version 1.4

This will be the last major update for some time as i have little free time these days!!!

A reset feature has been added, the eeprom data may now be reset byholding in vfo a/b while powering on untill 3 quick beeps are heard(takes about 5 seconds, there is a warning beep at 2 seconds)

JAL Source (1.5 beta)
Modified f452_20.jal lib file (for jal-0.4.59)
Modified jpic16.jal lib file (for jal-0.4.59)
Pre-Compiled HEX File (1.4 compiled with jal-0.4.59)
1st LO Diagram
CPU Adaptor PCB

The code is released under the GNU General Public License

A port to c (ccs pch compiler) has been done by Giorgio I6MAT ft757gx.c

For a programmer i recommend IC-Progusing a simple JDM based programmer interface (see ic-prog site)adapted for the 40 pin pic. The only connections required are GND(12& 31) VDD(11 & 32) RB6(39) RB7(40) & MCLR(1) (on the 18 pinsocket these are GND(5) VDD(14) RB6(12) RB7(13) & MCLR(4) )

For some pictures of my adaptor pcb click here.

Its been a very long time since i have worked on this code. If you have any questions feel free to email me and i will try my best to answer your question.

© Daniel Keogh 2010
vk2trp <at> tpg <dot>com <dot> au