top of page
MK3870N/14246 for Philips 22AH106 / 22AH799
This project addresses a common issue with the MK3870N microcontroller in Philips 22AH106 and 22AH799. The newly developed PCB with STM8S105 microcontroller replaces the original IC, enhancing the functionality of the device and adding several new features to improve performance and usability.
PCB with STM8S105 microcontroller
J3 is ST-LINK interface (2.54 mm header).
J4 is IRC input (S3B-PH-K-S with 2 mm pitch).
J5 (UART) and J6 are not used in current the configuration.
The PCB inside the control module
The right part of the PCB with IR receiver should be cut off and installed under the black sheet that covers the front panel PCB.
It is better not to install the JR1 (the connector near UR1) but solder the wires directly into the PCB.
IR receiver on the front panel PCB
Description of some functions usage
Station Memory
To store a frequency in a memory cell:
1. Press the STORE button.
2. Press the number of the desired station.
To clear a memory cell:
1. Select the desired station.
2. Press and hold the STORE button until the station number disappears.
If you manually tune to a frequency that is already stored in memory, the corresponding memory cell number will be displayed to prevent duplicate storage.
Direct frequency input
1. Select the desired band: FM, MW or LW.
2. Press the selected band button (FM, MW or LW) again.
3. The display will show _ _ _ _ _ allowing you to enter the frequency using the numeric buttons.
How to Set Up the Remote Control
You can use any remote control with NEC, RC5/RC6, Sony or JVC protocols.
Follow these steps to set functions with existing buttons on the front panel:
1. Turn off the tuner/receiver.
2. Press and hold STORE button until "o" appears in the memory display window.
3. Press "1" to enter Programming Option 1.
4. "Irc" will appear on the main display, indicating that the device is waiting for the IRC command.
5. Press the button on the remote control that you want to use.
6. If the remote control is compatible and the device recognizes the command, the display will show "bttn", indicating that the device is waiting for the corresponding front panel button to connect it to the chosen IRC command.
7. Press the desired button on the front panel.
8. The device will display "Irc" again, indicating it is ready for another remote control command.
9. Repeat the steps 4-8 for all desired commands.
Follow these steps to set functions without existing button on the front panel:
1. Turn off the tuner/receiver.
2. Press and hold STORE button until "o" appears in the memory display window.
3. Press "2" to enter Programming Option 2.
4. Use steps 4-8 from the previous description using the following buttons on the front panel:
Press "1" for Tuning+ (Encoder is not active in the StBy mode)
Press "2" for Tuning- (Encoder is not active in the StBy mode)
Press "3" for Programs+
Press "4" for Programs-
Press "5" for TAPE (the command is used in 22AH799)
Press "6" for PU (the command is used in 22AH799)
To exit the programming mode, press STORE button or turn on the device.
How to flash STM8S105 microcontroller
If you are using the ST-LINK V2 adapter as in the picture below, please, check the following.
Slightly move the metal enclosure to the USB connector to open the adapter and check the contacts of the IDC connector at the bottom side of the PCB. If they are not covered, use any isolation material to cover them. Sometimes the contacts touch the metal enclosure and cause a problem.
Download and install ST-LINK driver and programmer from ST website (simple registration needed):
1. STSW-LINK009 (ST-LINK driver)
https://www.st.com/en/development-tools/stsw-link009.html
2. STVP-STM8 (ST Visual Programmer STM8
https://www.st.com/en/development-tools/stvp-stm8.html
Open ST Visual Programmer.
Go to Configure -> Configure ST Visual Programmer.
Set Hardware: ST-LINK, Port: USB, Programming Mode: SWIM and Device: STM8S105x4 (if STM32S105C4 is used) or STM8S105x6 (if STM32S105C6 is used).
Connect the microcontroller PCB to the ST-LINK programmer:
RS pin J3 to RST programmer pin
SW pin J3 to SWIM programmer pin
GND pin J3 to GND programmer pin
+5V pin J3 to 5.0V programmer pin (if the PCB is installed and powered from the tuner/receiver, no need to connect +5V from the programmer.
Be sure that PROGRAM MEMORY tab is active.
Open software file with .s19 extention.
Press Program the current tab button.
If there is no error indicated in the bottom part of the ST Visual Programmer, the microcontroller is ready to be installed.
bottom of page