Receive/transmit modes of operations
FIG. 5
| CCITT V23 |
| TRS | TXR1 | TXR2 | TRANSMITTED
BIT RATE (b/s) | RECEIVED
BIT RATE (b/s) | CLK
FREQUENCY(KHz) |
| 0 | 0 | 0 | 1200 | 1200 | 19.11 |
| 1 | 0 | 0 | 1200 | 75 | 19.11 |
| 0 | 0 | 1 | 600 | 75 | 9.56 |
| 1 | 0 | 1 | 600 | 600 | 9.56 |
| 0 | 1 | 0 | 75 | 1200 | 19.11 |
| 1 | 1 | 0 | 75 | 600 | 9.56 |
| 0 | 1 | 1 | 75 | 75 | 1.19 |
| BELL202 |
| TRS | TXR1 | TXR2 | TRANSMITTED
BIT RATE (b/s) | RECEIVED
BIT RATE (b/s) | CLK
FREQUENCY(KHz) |
| CLK* | 0 | 0 | 1200 | 1200 | 19.11 |
| CLK 8 | 0 | 1 | 1200 | 150 | 19.11 |
| CLK 8 | 0 | 1 | 1200 | 5 | 19.11 |
| CLK | 1 | 0 | 150 | 1200 | 19.11 |
| CLK | 1 | 1 | 150 | 150 | 2.39 |
| See note 1 | 1 | See note 1 | 5 | 1200 | 19.11 |
| 1 | 1 | 1 | Transmit
disabled | 1200 | 19.11 |
Clock output must be inverted and connected to TRS input.
NOTE 1 : In this mode the modulation is controlled by the TRS and TXR2
TRS = CLK & TXR2 = 0 TXD = 1 TXA = 387Hz
TRS = 1 & TXR2 = 1 TXD = 1 or 0, TXA = 0Hz
Frequency assignment
FIG.6
| CCITT V23 | TRANSMITTED | TXD
BIT RATE b/s | TRANSMITTED
FREQUENCY Hz |
| 75 | 1 | M | 390 |
| 75 | 0 | S | 450 |
| 600 | 1 | M | 1300 |
| 600 | 0 | S | 1700 |
| 1200 | 1 | M | 1300 |
| 1200 | 0 | S | 2100 |
| BELL 202 | TRANSMITTED | TXD
BIT RATE b/s | TRANSMITTED
FREQUENCY Hz |
| 150 | 1 | M | 387 |
| 150 | 0 | S | 487 |
| 1200 | 1 | M | 1200 |
| 1200 | 0 | S | 2200 |
| 5 | See note 1 | M | 387 |
| | S | 0 |
NOTE 1 : In this mode the modulation is controlled by the TRS and TRX2 inputs
TRS = CLK & TXR2 = 0 TXD = 1 TXA = 387 Hz
TRS = 1 & TXR2 = 1 TXD = 1 or 0 TXA = 0 Hz
