MD1 888P

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Calculators: Handheld: MD1 888p

		Size (approx):	66mm x 113mm x 23mm (max) (w,h,d) Weight 78g excluding batteries.
		Power:	9.0V DC, 1 x PP3 size battery. It does not accept an adapter.
		Case:	The main body is made from dark brown and beige glossy plastic with a matching matt plastic dark brown keyboard surround. The red plastic display filter is raised, tilted and concave over the digits. It gives a bright display but with limited angle of view. On this filter is a raised recess that holds a black printed metallic sticker with the brand and model number. The keys are short travel with a positive click.
		.Display:	8 digit red LED with individual bubble lens, no ninth digit
		Features:	Four standard functions and percentages
		Age:	1976
		Manufacturer:	MD1, made in Singapore, serial number 09963.
		Comments:	For a little-known calculator name this is quite a well built pal-sized calculator. I presume that it is related to the MD2 888m as it would otherwise be difficult to tell if the brand was MDI. The logic is average with good recovery but let down by the pseudo fixed decimal bug and seven digit negative numbers.

Components:	1 x cpu: IEE RC5000 546, 40 pin DIL, 0.6" width black plastic 1 x 8 digit LED unit with individual bubble lens 1 x capacitor 2 x resistors
Boards:	The keyboard assembly is self contained and sits loose in the case. It is connected to the main board (Ref: U102) with 10 strong copper wires. The whole assembly can be easily removed as one unit.
Construction:	Remove the two screws from the back and the rear hinges off from the bottom easily.

Logic comments:	The (CE) key is actually a “C/CE” key, the first press can be used to clear the last entry whilst a second press clears the calculator completely
	Input overflow is suppressed, keying in a ninth digit is ignored
	Negative numbers are represented with a “-“ sign in the immediate left digit but as there is no ninth digit you are limited to seven digit negative numbers
	The negative sign will replace the leading zero in a number less than one: so -0.3 will display as “-.3”
	There is automatic constant on all four functions
	Overflow shows the result with all decimal points alight which is recoverable using (CE)
	Divide by zero shows “0.0.0.0.0.0.0.0.” which is recoverable using (CE)
	It suffers the pseudo fixed decimal bug: key in (1)(+)(.)(0)(0)(0)(=) to give “1.000” which remains a fixed three digit number until you need more digits or use multiply or divide