X-Git-Url: https://vault307.fbx.one/gitweb/micorpython_ir.git/blobdiff_plain/12683170548778e5d933f2f2052164547cc15113..7156dff5bcd19a1debf7db1ffd4add94e010c66f:/TRANSMITTER.md

diff --git a/TRANSMITTER.md b/TRANSMITTER.md
index 7a70cca..c76995b 100644
--- a/TRANSMITTER.md
+++ b/TRANSMITTER.md
@@ -16,7 +16,16 @@ are arbitrary: X3 and X4 are used. The driver uses timers 2 and 5.
 On ESP32 the demo uses pin 23 for IR output and pins 18 and 19 for pushbuttons.
 These pins may be changed. The only device resource used is `RMT(0)`.
 
-## 1.1 Pyboard Wiring
+On Raspberry Pi Pico the demo uses pin 17 for IR output and pins 18 and 19 for
+pushbuttons. These pins may be changed. The driver uses the PIO to emulate a
+device similar to the ESP32 RMT. The device driver is
+[documented here](./RP2_RMT.md); this is for experimenters and those wanting to
+use the library in conjunction with their own PIO assembler code.
+
+## 1.1 Wiring
+
+All microcontrollers require an external circuit to drive the LED. The notes
+below on specific microcontrollers assume that such a circuit is used.
 
 I use the following circuit which delivers just under 40mA to the diode. R2 may
 be reduced for higher current.  
@@ -41,13 +50,19 @@ updated to use it. The same circuits as above may be used to connect to pin 23
 available on the ESP32 `RMT` object, so any alternative circuit must illuminate
 the LED if the pin state is high.
 
+## 1.3 RP2 Wiring
+
+There is no `active_high` option so the circuit  must illuminate the LED if the
+pin state is high, as per the above drivers. Test programs use pin 17, but this
+can be reassigned.
+
 # 2. Dependencies and installation
 
 ## 2.1 Dependencies
 
 The device driver has no dependencies.
 
-On ESP32 a firmware version >= V1.14 is required. The Loboris port is not
+On ESP32 a firmware version >= V1.17 is required. The Loboris port is not
 supported owing to the need for the RMT device and other issues.
 
 The demo program uses `uasyncio` primitives from
@@ -80,7 +95,8 @@ Instructions will be displayed at the REPL.
 
 # 3. The driver
 
-This is specific to Pyboard D, Pyboard 1.x (not Lite) and ESP32.
+This is specific to Pyboard D, Pyboard 1.x (not Lite), ESP32 and Raspberry Pi
+Pico (RP2 architecture chip).
 
 It implements a class for each supported protocol, namely `NEC`, `SONY_12`,
 `SONY_15`, `SONY_20`, `RC5` and `RC6_M0`.  Each class is subclassed from a
@@ -101,6 +117,13 @@ from ir_tx.nec import NEC
 nec = NEC(Pin(23, Pin.OUT, value = 0))
 nec.transmit(1, 2)  # address == 1, data == 2
 ```
+Basic usage on Pico:
+```python
+from machine import Pin
+from ir_tx.nec import NEC
+nec = NEC(Pin(17, Pin.OUT, value = 0))
+nec.transmit(1, 2)  # address == 1, data == 2
+```
 
 #### Common to all classes
 
@@ -149,7 +172,7 @@ skipping validation.
 | RC6_M0   | 6.0ms | 2.0ms   |
 | MCE      | 6.7ms | 2.0ms   |
 
-#### NEC class
+#### NEC class (also Samsung)
 
 Class `NEC`. Example invocation:
 ```python
@@ -167,6 +190,16 @@ the complement for values < 256.
 
 A value passed in `toggle` is ignored.
 
+For Samsung protocol set the `samsung` class variable `True`:
+```python
+from ir_tx.nec import NEC
+NEC.samsung=True
+```
+Samsung remotes do not seem to use repeat codes: the sample I have simply
+repeats the original code.
+
+Thanks are due to J.E.Tannenbaum for information about the Samsung protocol.
+
 #### Sony classes
 
 Classes `SONY_12`, `SONY_15` and `SONY_20`. Example invocation: