Update x230.md

Added description how to wire the Pomona Flash Clip to the Raspberry Pi

docs/coreboot/x230.md

@@ -45,8 +45,108 @@ the following parts are needed to build a Coreboot flashing devices:
   https://www.digikey.de/product-detail/de/pomona-electronics/5250/501-1311-ND/745102
 
 ## physical setup (FIXME!)
-the information how to connect the Pomodo Clip to the rapsberry pi has to be included here.
+using a Raspberry Pi 3 Model B V1.2 the GPIO Layout looks like this:
+(Hint you can get a very good overview of the layout by entering the 'pinout' command on your pi:
+'''
+,--------------------------------.
+| oooooooooooooooooooo J8     +====
+| 1ooooooooooooooooooo        | USB
+|                             +====
+|      Pi Model 3B V1.2          |
+|      +----+                 +====
+| |D|  |SoC |                 | USB
+| |S|  |    |                 +====
+| |I|  +----+                    |
+|                   |C|     +======
+|                   |S|     |   Net
+| pwr        |HDMI| |I||A|  +======
+`-| |--------|    |----|V|-------'
 
+Revision           : a02082
+SoC                : BCM2837
+RAM                : 1024Mb
+Storage            : MicroSD
+USB ports          : 4 (excluding power)
+Ethernet ports     : 1
+Wi-fi              : True
+Bluetooth          : True
+Camera ports (CSI) : 1
+Display ports (DSI): 1
+
+J8:
+   3V3  (1) (2)  5V    
+ GPIO2  (3) (4)  5V    
+ GPIO3  (5) (6)  GND   
+ GPIO4  (7) (8)  GPIO14
+   GND  (9) (10) GPIO15
+GPIO17 (11) (12) GPIO18
+GPIO27 (13) (14) GND   
+GPIO22 (15) (16) GPIO23
+   3V3 (17) (18) GPIO24
+GPIO10 (19) (20) GND   
+ GPIO9 (21) (22) GPIO25
+GPIO11 (23) (24) GPIO8 
+   GND (25) (26) GPIO7 
+ GPIO0 (27) (28) GPIO1 
+ GPIO5 (29) (30) GND   
+ GPIO6 (31) (32) GPIO12
+GPIO13 (33) (34) GND   
+GPIO19 (35) (36) GPIO16
+GPIO26 (37) (38) GPIO20
+   GND (39) (40) GPIO21
+
+For further information, please refer to https://pinout.xyz/
+'''
+
+Layout of pins if you look on the pi and, the GPIO pins are located on the left side, so that USB and ethernet ports are at the top:
+'''
+        | USB |  | USB |    | RJ45 |
+        |     |  |     |    |      |
+        +-----+  +-----+    +------+
+
+e       +-----+
+d       | o o <-  GND
+g       | o o |
+e       | o o |
+        | o o |
+o       | o o |
+f       | o o |
+        | o o |
+R       | o o |
+a  CS  -> o o <-  CLK
+s       | o o <-  MISO
+p       | o o <-  MOSI
+b       | o o <-  3.3V 
+e       | o o |
+r       | o o |
+r       | o o |
+y       | o o |
+        | o o |
+P       | o o |
+i       | o o |
+        | o o |
+        +-----+
+'''
+We need to connect 6 pins to the Pomona SOIC8 5250 Test Clip using the jumper cables.
+you can take any color you want, to make it simpler for you, I'll add the colors I have used:
+
+connect 6 jumper cables to the raspberry pi GPIO pins:
+
+- GND	black
+- CS	green
+- CLK	gray
+- MISO	white
+- MOSI	purple
+- 3.3V	blue
+
+Now connect the other end of the jumper cables to the Pomona Clip:
+'''
+    MOSI (purple) 5 =|  |= 4  GND  (black)
+     CLK (gray)   6 =|  |= 3  NC   (empty)
+      NC (empt    7 =|  |= 2  MISO (white)
+3.3V/VCC (blue)   8 =|_*|= 1  CS   (green)
+                              (dot on top of the chip)
+'''
 
 ## Procedure