update readme; add images gallery

README.md

@@ -1,7 +1,13 @@
-## ZX-Uno.1010
+## ZX-UNO.1010
 10x10cm PCB variant of ZX-Uno project
 
-[![photo](images/revA.small.webp)](images/revA.webp?raw=true)
+[![photo](images/thumb.rev.D.front.webp)](images/README.md)
+
+[![photo](images/thumb.rev.D.side.webp)](images/README.md)
+
+[[More photos]](images/README.md)
+
+
 
 Tech specs:
 - Fully compatible with ZX Uno v4.1 and ZX-Uno VGA 2M
@@ -15,7 +21,8 @@ Tech specs:
 - Tape input via Bluetooth module or ordinary 3.5 jack
 - MIDI
 - WiFi module
-- MicroUSB power supply
+- RTC (starting from rev.B)
+- Type C (starting from rev.D) or MicroUSB power supply
 - Board optimized for G738 and G706 cases
 
 FAQ on official site: [link](https://uto.speccy.org/zxunofaq_en.html)
@@ -25,6 +32,44 @@ Some random photos: [link](https://cloud.err200.net/index.php/s/73TR85tYZkMm8Ax?
 ### Changelog
 * Rev.A - first release ([main pcb errata](pcb/rev.A/ERRATA.txt) and [covers errata](pcb_covers/rev.A/ERRATA.txt)).
 * Rev.A1 - fixes all known issues of rev.A.
+* Rev.B:
+    * added RTC
+    * changed second joystick port wiring - in rev.A it's has been wired like in ZXUNO-VGA2M, but now it's wired like Joysplitter, which is officially supported way
+    * joysticks are now powered by +5V rail instead of +3.3V - this should improve compatibility with various RF gamepads
+    * optimized SAM2695 footprint for hand soldering
+    * added opamp for proper MIDI sound mixing
+    * added buffer in DAC circuit
+    * added separate LDO for SD card and WiFi module
+    * added resistor between WiFi's GPIO15 and GND to prevent IC heating
+    * remove beeper (which wasn't used anyway)
+    * improved power distribution for FPGA chip
+    * pcb corners are rounded now
+    * experimental tape-in circuit
+* Rev.C:
+    * added dedicated LDO for audio to improve noise floor
+    * added optional capacitor for NTSC quartz stability
+    * added missing decoupling capacitor on RTC power rail
+    * added current-limiting resistors after opamp on sound output
+    * changed R76, R80 from 10kΩ to 8.2kΩ
+    * changed U10 opamp from NE5532 to LMV358 as it better suited for low-voltage operation
+    * 3mm front leds replaced by 5mm
+    * experimental reset circuit based on MAX809
+    * reverted to old tape-in circuit
+* Rev.D:
+    * used USB Type C instead of Micro USB
+    * PJ-320 3.5mm jack replaced by PJ-322
+    * added solder jumper to select 3.5mm jack CVBS pinout
+    * MIDI synthesizer U6 uses clean analog power rail now
+    * improved W25Q128 footprint to able to install IC in WSON package
+    * some minor PCB layout changes to reduce WiFi interference
+    * reverted to old reset circuit
+* Rev.D1:
+    * changed R16 from 220Ω to 1kΩ to reduce power led bightness
+    * changed R70, R71 from 10kΩ to 12kΩ to improve balance with AY
+    * changed C51 from 100nF to 1uF to improve audio noise floor
+    * changed C13 value as some quartz failed to start with 4.3pF load
+    * changed U17 from LP2985-3.3 to TPS7A2033PDBVR due to better PSRR
+    * changed U15 from 74LVC2G34 to 74LVC2G04 as it's more common in my projects
 
 ### References
 * ZX Uno official site: [link](https://zxuno.speccy.org/index_e.shtml)

images/README.md

@@ -0,0 +1,18 @@
+# Gallery
+
+## Revision D
+[![photo](thumb.rev.D.front.webp)](https://raw.githubusercontent.com/UzixLS/zxuno1010-board/refs/heads/master/images/rev.D.front.webp)
+[![photo](thumb.rev.D.back.webp)](https://raw.githubusercontent.com/UzixLS/zxuno1010-board/refs/heads/master/images/rev.D.back.webp)
+
+[![photo](thumb.rev.D.top.webp)](https://raw.githubusercontent.com/UzixLS/zxuno1010-board/refs/heads/master/images/rev.D.top.webp)
+[![photo](thumb.rev.D.side.webp)](https://raw.githubusercontent.com/UzixLS/zxuno1010-board/refs/heads/master/images/rev.D.side.webp)
+
+## Revision C
+[![photo](thumb.rev.C.front.webp)](https://raw.githubusercontent.com/UzixLS/zxuno1010-board/refs/heads/master/images/rev.C.front.webp)
+[![photo](thumb.rev.C.back.webp)](https://raw.githubusercontent.com/UzixLS/zxuno1010-board/refs/heads/master/images/rev.C.back.webp)
+
+[![photo](thumb.rev.C.top.webp)](https://raw.githubusercontent.com/UzixLS/zxuno1010-board/refs/heads/master/images/rev.C.top.webp)
+[![photo](thumb.rev.C.side.webp)](https://raw.githubusercontent.com/UzixLS/zxuno1010-board/refs/heads/master/images/rev.C.side.webp)
+
+## Revision A
+[![photo](thumb.rev.A.webp)](https://raw.githubusercontent.com/UzixLS/zxuno1010-board/refs/heads/master/images/rev.A.webp)