trevordes

Pete, Thank you, you nailed it. The compiler performs all multiplications/divisions in FP if any of the terms is FP so the denominator terms worked fine with just the first term as a float and apparently AC_Lat_int*90 did not cause an integer overflow, but obviously AC_Long_int*360 was resulting in an integer overflow. Changing to (AC_Long_int*360.0) forced the calculation into FP and prevented the overflow. I have found the module user section thank you. I know if this was all I wanted, the token var would have provided the answer. However, this is just the first preliminary step in providing an Air-to-air radar using the AI tables, so I figured on using this as a "simpler ??" exploration of the UIPC interface, before diving into the AI tables. Trevor.

Pete, Here goes with C code extracts. From Gauge Heading declarations: GAUGE_HEADER_FS700(GAUGE_W, display_gauge_name, &display_list, \ display_mouse_rect, display_cb, 0, 0, 0); char chTime[3]; BOOL FS_read_ok; FLOAT64 AC_Lat; FLOAT64 AC_Long; Callback function void FSAPI display_cb(PGAUGEHDR pgauge, int service_id, \ UINT32 extra_data) { UINT32 dwResult; SINT64 AC_Lat_int, AC_Long_int; switch(service_id) { case PANEL_SERVICE_PRE_INSTALL: break; case PANEL_SERVICE_POST_INSTALL: FSUIPC_Open(SIM_ANY,&dwResult); break; case PANEL_SERVICE_PRE_INITIALIZE: break; case PANEL_SERVICE_PRE_UPDATE: FS_read_ok = TRUE; if (!FSUIPC_Read(0x238, 3, chTime, &dwResult) || !FSUIPC_Read(0x560, 8, &AC_Lat_int, &dwResult) || !FSUIPC_Read(0x568, 8, &AC_Long_int, &dwResult) || !FSUIPC_Process(&dwResult)) FS_read_ok = FALSE; else { AC_Lat = AC_Lat_int * 90 /( 10001750.0 * 65536 * 65536 ); AC_Long = AC_Long_int * 360 / (65536.0 * 65536 * 65536 * 65536); } break; case PANEL_SERVICE_PRE_DRAW: break; case PANEL_SERVICE_PRE_KILL: FSUIPC_Close(); break; } } Lat display callback (Works fine N or S Lat) FLOAT64 FSAPI lat_string_cb( PELEMENT_STRING pelement ) { UINT32 deg; float min; char n_s; if (FS_read_ok) { if (AC_Lat >= 0) n_s = 'N'; else { n_s = 'S'; AC_Lat = - AC_Lat; } deg = floor(AC_Lat); min = ( AC_Lat - deg) * 60; sprintf(pelement->string, "%c%2d*%6.3f",n_s, deg, min); } return 1.0; } Long display callback FLOAT64 FSAPI long_string_cb( PELEMENT_STRING pelement ) { UINT32 deg; float min; char e_w; if (FS_read_ok) { if (AC_Long >= 0) e_w = 'E'; else { e_w = 'W'; AC_Long = - AC_Long; } deg = floor(AC_Long); min = ( AC_Long - deg) * 60; sprintf(pelement->string, "%c%03d*%6.3f",e_w, deg, min); } return 1.0; } For Ohakea AFB NZ E175*23.42' (From FS9 readout) displays E000*23.421 For Vance AFB OK W97*55.39' displays E000* 4.609 System is running WinXPpro compilation using Visual Studio 6 IDE (VC98) Trevor

Pete, I am developing a gauge which I want to read the present position. I can read 8 bytes from offset 0x0560 into a SINT64 variable and process it in accordance with the instructions in the SDK into a FLOAT64 variable and this provides the Latitude fine. However, when I try similar process with 8 bytes from 0x0568 for the longitude the result comes out as 0.nnnnn where .nnnnn * 60 is the correct number of minutes for East Longitude, and 60 - (.nnnnn * 60) is the correct number of minutes for West Longitude, but in all cases the number of degrees is always 0 and the actual answer is always positive. Any suggestions you have would be appreciated. Trevor