Modification to put in MUD slot / M9312
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Errata
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Silk: J16 "PWR +5V=USB":
(connect wenn only USB cable connected, OR only +5V
disconnect when both +5V and USB.)


Silk: "KY11" -> "KY11-LB"

Share KY11 MSCP23017 with KM11
use additional inputs to monitor inputs from KY11-LB controller


2024-08
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Board name schanged to "M93X2" .. it is 9302 and 9312

DIP switch accessible from front.

FASTON und FASTONGND for external boot switch
(aus BlinkenBone 11/70 adapter übernehmen)
BOOTSWITCH 22k pullup
BOOTSWITCH RETURN über 1K an GND



EEPROM
1MBit = 128kx8 I2C eeprom drauf
Reichelt 24LC1025 I/P
A0,A1 = GND, A2 to vcc,
I2C addr 0 1010<block>00 =0xa0
MCP23017 have 0x20+x

DCLO U12.2 to Arduino Pin 11 D8 ex AUX0
ACLO U12.2 to Arduino Pin 12 D9 ex AUX1

M.U.D.: GND nur an AC2, AT1, BC2, BT1
Cut traces:
GND: AN1,AP1,AR1,AS1, AB2,AV2, BD1,BE1, BB2,BV2

M.U.D:
Solder bridges for BG*, NPG* (open for MUD!)
  -> 2x5 Jumperblock or 2x5 steckbare 0-Ohm SIP Leiste
BG4,5,6,7 = BE2, BB1, BA1, AV1
NPG = AU1

BBSY writeable
U4.13 an UNIBUS BBSY_L
U4.11,U4.12 an BBSY_OUT an MCP23017-0.3 GPB4 = pin 5

Silk label U3 8837
Silk: "µTracer11 M9302probe"


2024-03
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I2C pullups
minimal for 1MHz speed
DESIGNING-WITH-I2C-BUS-DEVICES.pdf
-> 1.7kohm, two parallel -> R1-R4 10KOhm-> 3.3kOhm
SDA is sunk by MEGA4809 and MCP23017. SCL only by MEGA.


Signal C1_OUT
U12.6 MCP0.3 GPB5 =>   U4.8,9
U4.10 -> "C1" pin header


U13, U14 74LS374
Inputs/Outputs vertauscht !!!

Signal SACK_OUT
U12.7 -> U4 5,6
U4.4 -> JP1.2

U7: 74ls00 -> 74ls86
Signal LATCH_DATA
MCP0.2 GPB7 -> U7B.4


Errata
Silk:
"C2" "100nF"
R9, R10: "1K"
LED D1, D2: Polarity


2024-02
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