Memory map for Yaesu VX-3R
First ten bytes, sent by TRX in clone mode, contain kind of its ID. Then it waits for the PC to confirm. After "06h" is received, it is sent back and followed by main memory content - 32575 bytes with checksum byte at the end.
For further analysis and for my project, let's assume that the binary file with memory image contains everything sent by the radio. So we have: 10 bytes long header, confirmation byte, 32575 bytes of content and checksum byte. Bytes counting starts with "0".
General memory areas
| From | To | Purpose | Remarks |
|---|---|---|---|
| 0h | 9h | TRX ID | |
| 10h | 10h | Confirmation (06h) | |
| C0Ch | CFBh | "Home channels" frequencies | 12 x 20 bytes |
| CFCh | DEBh | Current frequencies in VFO mode | 12 x 20 bytes |
| 20CBh | 22F0h (?) | Flags of cells existence and "hidden" attribute | |
| 244Bh | Stored frequencies | 900 x 20 bytes | |
| 726Bh | 7A3Ah | Scanning ranges (L1, U1, ..., L50, U50) | |
Single memory cell
Every frequency stored to memory is described on 20 bytes. W tabeli poniżej wyjaśnione jest znaczenie poszczególnych pól (w nawiasach kwadratowych podane są wartości flag dla poszczególnych opcji).
| Offset | Bit | Purpose | Remarks |
|---|---|---|---|
| 0h | |||
| 1h | 0-3 | Frequency step: 5 [0h] / 8,3 [1h] / 10 [2h] / 12,5 [3h] / 15 [4h] / 20 [5h] / 25 [6h] / 50 [7h] / 100 [8h] kHz | |
| 4-5 | Repeater shift: simplex [0h] / - [10h] / + [20h] / odd split [30h] | ||
| 6-7 | Modulation: FM [0] / AM [40h] / WFM [80h] | ||
| 2h-4h | RX frequency in kHz | 1) | |
| 5h | 0-2 | SQ TYP: off [0h] / TONE [1h] / TN-SQL [2h] / DCS [3h] / RV_TN [4h] / PR FRQ [5h] / PAGER [6h] / MESSAGE [7h] | |
| 6-7 | TX Power: LOW [0] / HI [C0h] | ? | |
| 6h-Bh | Alpha tag. If it should be displayed, first byte is incremented by 80h (128dec). ?Empty? alpha tag is marked with FFh on all bytes. |
||
| Ch-Eh | TX frequency (odd split) or repeater shift in kHz | 1) | |
| Fh | CTCSS tone: 67,0 [0h] / 69,3 [1h]/ 71,9 [2h] / 74,4 [3h] / 77,0 [4h] / 79,7 [5h] / 82,5 [6h] / 85,4 [7h] / 88,5 [8h] / 91,5 [9h] / 94,8 [Ah] / 97,4 [Bh] / 100,0 [Ch] / 103,5 [Dh] / 107,2 [Eh] / 110,9 [Fh] / 114,8 [10h] / 118,8 [11h] / 123,0 [12h] / 127,3 [13h] / 131,8 [14h] / 136,5 [15h] / 141,3 [16h] / 146,2 [17h] / 151,4 [18h] / 156,7 [19h] / 159,8 [1Ah] / 162,2 [1Bh] / 165,5 [1Ch] / 167,9 [1Dh] / 171,3 [1Eh] / 173,8 [1Fh] / 177,3 [20h] / 179,9 [21h] / 183,5 [22h] / 186,2 [23h] / 189,9 [24h] / 192,8 [25h] / 196,6 [26h] / 199,5 [27h] / 203,5 [28h] / 206,5 [29h] / 210,7 [2Ah] / 218,1 [2Bh] / 225,7 [2Ch] / 229,1 [2Dh] / 233,6 [2Eh] / 241,8 [2Fh] / 250,3 [30h] / 254,1 [31h/49dec] | ||
| 10h | DCS tone | ||
| 11h | usually 00h lub 0Dh | unknown | |
| 12h | |||
| 13h | Flag 8h = AUTO modulation Flag 10h = AUTO frequency step |
1) frequencies are stored in BCD notation (Binary Coded Decimal), so they are easly readable in any hex-editor.