Differences

This shows you the differences between two versions of the page.

--- projects:yamaha_r840 [2025/10/23 22:52] – [System Connector] admin
+++ projects:yamaha_r840 [2025/12/01 07:53] (current) – admin
@@ Line 1: / Line 1: @@
+~~META:
+title=Yamaha MCR-840
+description=Yamaha R-840 repair and hacking
+keywords=SEO, dokuwiki, disassembly, yamaha, R840, music, hack, hacking, audio, iPod, system connector, repair
+~~
 ====== Yamaha Audio Amp/Receiver ======
 ===== Yamaha MCR-840 =====
@@ Line 18: / Line 24: @@
 Read the block diagram from service manual: {{ :projects:yamaha:block-diagram.pdf |}} \\
+I have re-uploaded the necessary pages from service manual seen in hifi-forum threads for capacitor and resistor repair: {{ :projects:yamaha:yamaha-r840-repair.zip |}} \\
 === Capacitor ===
@@ Line 42: / Line 49: @@
 Probably more Yamaha systems can be repaired in that scheme. \\
+==== Remote control ====
+There is nothing much to say. It is a simple iR remote control. The main IC is marked "2428662 03160". \\
+iR codes for R840 can be found on page 80/150 of service manual (next to remote control schematic). \\
+Here is an unspectacular insight: \\
+{{:projects:yamaha:rc1.jpg?125|}}
+{{:projects:yamaha:rc2.jpg?200|}} \\
+I have taken the pictures so you can see at which positions the holding clips are - don't forget about the single screw in the battery compartment.
+The buttons and their layout of remote control for DVD and BD versions differ slightly. \\
 ==== Disc Player manual eject ====
 The players only turn on with system connector plugged into R840 amp (see [[projects:yamaha_r840#the_round_one|below how to simulate system connector]]). \\
@@ Line 53: / Line 68: @@
 === the round one ===
-The system connector is used for a connected disc player. It enables the RCA-input for the player and also transfers signals like power-toggle. \\
+The system connector is used for a connected disc player. It enables the RCA-input for the player and also transfers signals like power-toggle and remote control signals. \\
 It uses proprietary 8‑pin DIN connector (find the cable under name "MINI DIN 8-PIN MD8"). \\
@@ Line 67: / Line 82: @@
 {{:projects:yamaha:system-connector-connection.png?direct&200|}}
+MD8 "ZP512100" cable is not only used by MCR-840 but also various other systems like MCS1330 (R1330 + CD1330). As I do not own anything else but R840, I cannot say if other devices use the same protocol or even pinout! Always check yourself before. \\
 == communication signal ==
@@ Line 79: / Line 96: @@
 === the flat one: writing port ===
-Yamaha devices use a so called "writing port", a flat cable, e.g. for flash ucom via RS232-adapter. It is known for updating firmware over PC software (which we don't have). \\
+This is just an FYI, IMO we cannot do anything useful with the port. \\
+Yamaha devices use a so called "writing port", a flat cable, e.g. to flash ucom via RS232-adapter. It is known for updating firmware over PC software (which we don't have). \\
 R840 uses Renesas M16C/64 R5F3640DNFA MCU. Service manual states to use FlashSta.exe (which we don't have, neither R840_xxx.mot + R840_xxx.id firmware), FYI see [[https://www.renesas.com/en/document/mat/m16c-flash-starter-m3a-0806-users-manual?srsltid=AfmBOoouDn1Ckenn0l-1YUgHz2BwZHPVGnbNhIjZUAa85k5-iwqpdRbM|Renesas M16C flashing guide]]. If you still want to look into flashing M16C MCU go to
@@ Line 110: / Line 128: @@
 [[http://www.ipodlinux.org/Apple_Accessory_Protocol/]] \\
 [[https://github.com/xtensa/PodEmu/tree/master|xtensa/PodEmu: Android application that emulates iPod to use together with old 30-pins iPod serial interface]] \\
+[[https://xdaforums.com/t/app-3-0-podemu-connect-android-to-30pin-ipod-docking-station-or-car.3234840/|PodEmu on XDA]] \\
 [[https://github.com/xtensa/oap|xtensa/oap: Implementation of iPod serial communication protocol used in old 30-pin iPod interfaces]] \\
 [[https://github.com/oandrew/ipod-gadget|oandrew/ipod-gadget: iPod usb gadget for audio playback]] \\
@@ Line 138: / Line 157: @@
 ==== Yamaha Loudness ====
-#TODO upload loudness schematics \\
+Loudness compensation is used to maintain a balanced sound at different volume levels. At low listening volume levels, the bass drivers need to produce more sound pressure to be perceived at the same level as the mid and high frequencies.
+See a collection of schematics for loudness circuits here: [[http://www.hifi-forum.de/viewthread-71-12517.html]] \\
+{{:projects:yamaha:loudness-schaltung-yamaha.png?direct&200|}} \\
 #TODO software implementation of loudness \\
 #auto-volume level + auto-level loudness curve \\
@@ Line 181: / Line 204: @@
 === iR codes ===
-iR codes for R840 can be found on page 80/150 of service manual (next to remote control schematic). \\
 [[https://github.com/theCstokes/YamahaRemote/blob/master/IR_RX-V667-3067_rev0.0_Full.xls|yamaha V667 etc iR codes]] \\