Replace software TX/RX control with hardware PTT control #17
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- Add delay to account for switch path timing
| @@ -122,7 +122,7 @@ extern const uint8_t I2C_ADDR_XCVR; | |||
| /* | |||
| * Time management | |||
| */ | |||
| void delay(uint16_t n); | |||
| void delay(uint32_t n); | |||
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This was left in as an artifact of my earlier experimentation trying to make a configurable delay for people using RF switches that were triggered by PTT, and is not relevant to this PR. It should not affect functionality overall.
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Hi! |
| @@ -447,14 +481,16 @@ bool platform_poke(uint8_t addr, uint8_t reg, uint16_t val) { | |||
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| // TX requested so disable RXEN | |||
| if (reg == 0x30 && (val & (1 << 6))) { | |||
| P1_bit.no0 = 1; // P10 (RXEN) is high | |||
| //P1_bit.no0 = 1; // P10 (RXEN) is high | |||
| return false; // HW PTT override | |||
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I think #17 (comment) can be addressed by simply removing the return false statements here and on line 493. Alternatively, another AT command could be added to allow hardware, software, or a combination of PTT inputs. Is there any use case where both methods would be needed?
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I would recommend making it an "OR" logic. If either the serial command, OR the hardware pin are active, then put the AT1846 into transmit mode. If neither are active, then put the AT1846 into receive mode.
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I added this commit to my personal branch but have not tested it: 4b5f038 Is anyone able to test if this behaves well using both hardware and software PTT? |
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Added with 4b5f038. |
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Code review: This part of the change looked reasonable. |
Existing projects using the SA868 will be using the PTT pin for TX/RX control. I propose locking out this control via UART, and instead allowing the module to read the state of the PTT pin and enable/disable amplifiers and issue I2C commands to the RDA1846S. My implementation works by polling the state of PTT on P22 (necessary given no interrupt available on P22) and attempts to optimize performance by detecting the state of PTT, executing TX/RX changes only on that state change. Any attempts to manually set bits 5 or 6 of reg 0x30 via UART will be treated as an error.