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Characterization of MK6010 Family Single-chip Calculator Circuits

The DCM-50A (PLAYGROUND) supports the Characterization of the the DCM-50A Playground MK6010 Adapter mounted on top of the DCM-50A PG Digit Inverter Frame Carrier and supported by the DCM-50A PG KBD102 Keyboard configured to MK6010 Mode. The voltage selector jumper on the MK6010 Adapter must be set to the appropriate voltage. The optional DCM-50A Playground Digilent I/O Extender supports Characterization and Reverse-engineering of MK6010 Family single-chip calculator circuits.

MK5011

Device-under-Test:

• Package Markings Top: MOSTEK MK5011P 7306KEG
• Package Markings Bottom:
• Donor Calculator: Unitrex 1200 (Type 37, Rev. 4C), May 1973

Keyboard: The Unitrex 1200 makes use of a keyboard assembly with 17 spring-loaded plastic keys pushing two fingers of stamped sheet-metal pieces soldered perpendicular on a single-sided phenolic PCB together. The 10 number keys are connected with a diode matrix to the key inputs KN1 to KN4 (Numbers) of the MK5011 while the 7 function keys are connected to its discrete key inputs. The 4-position sliding switch for the Decimal Point selection is connected with a diode matrix to the DP1 and DP2 inputs of the MK5011.

Keyboard Matrix of the Unitrex 1200 (Type 37, Rev. 4C):

MK5011

KEY KN8 KN4 KN2 KN1

[1] - - - log.1

[2] - - log.1 -

[3] - - log.1 log.1

[4] - log.1 - -

[5] - log.1 - log.1

[6] - log.1 log.1 -

[7] - log.1 log.1 log.1

[8] log.1 - - -

[9] log.1 - - log.1

[0] log.1 - log.1 -

	MK5011
KEY	KC	KCE	KD	KM	KS	KAE	KP
[C]	log.1	-	-	-	-	-	-
[CE]	-	log.1	-	-	-	-	-
[÷]	-	-	log.1	-	-	-	-
[×]	-	-	-	log.1	-	-	-
[−]	-	-	-	-	log.1	-	-
[+=]	-	-	-	-	-	log.1	-
[.]	-	-	-	-	-	-	log.1

	MK5011
SWITCH	DP2	DP1
[4-3-2-0]	-	-
[4-3-2-0]	-	log.1
[4-3-2-0]	log.1	-
[4-3-2-0]	log.1	log.1

Display: The Unitrex 1200 makes use of a Japan Radio Corporation (JRC) Septanix J4962E Planar Neon Gas Discharge Display (Panaplex-style) connected with two Kyodo KH-6225 Digit Driver Modules and 12 high-voltage capacitors as level shifters to the twelve Digit Outputs D1 to D12 of the MK5011 and one Kyodo KH-6259 Segment Driver Module connected to the Segment Outputs SA to SG and SDP of the MK5011. The display is operated with approximately -180 Volts. An additional discrete orange miniature gas-discharge lamp is used as minus sign for negative numbers and connected with a transistor to the Sign output of the MK5011.

Display Layout:

JRC Septanix J4962E plus Lamp

The Segment drivers A-G and DP (Decimal Point) are connected to the JRC Septanix J4962E display in the pictured way.

Display Fonts:

Type	Calculator	Number Fonts	Decimal Separator	Thousands Separator	Entry Overflow	Calculating Overflow	Minus
MK5011	Unitrex 1200 (Type 37)			n.a.

Display scanning: Display scanning is performed in D1 → D12 direction at a rate of about 480 Hz:

• Digit Time = 4 Clocks = 0.160 ms @ CK=25 kHz
• Scan Time = 13 Digit Times (D1 to D13 with D13 a dead cycle) = 2.08 ms @ CK=25 kHz

If you have additions to the above article please email: joerg@datamath.org.

	MK5011
KEY	KN8	KN4	KN2	KN1
[1]	-	-	-	log.1
[2]	-	-	log.1	-
[3]	-	-	log.1	log.1
[4]	-	log.1	-	-
[5]	-	log.1	-	log.1
[6]	-	log.1	log.1	-
[7]	-	log.1	log.1	log.1
[8]	log.1	-	-	-
[9]	log.1	-	-	log.1
[0]	log.1	-	log.1	-