# Precision Measurement Central (2)

## printed circuit board and software suite

The solid base of the Precision Measurement Central (or ‘Elektor Meter’) is the powerful MSC1210 development system and an I2C LC display unit described elsewhere in this issue. This base and the software suite described this month will be used in a number of future projects employing the highly interesting MSC1210 microcontroller.First, however, we need to ‘wrap up’ the hardware side of things. In the previous issue (July/August 2003) we discussed the operation of the MSC1210 controller board along the lines of its circuit diagram. For lack of space in the first instalment we could not include the layout of the double-sided printed circuit board and the associated component lists. With a ‘thank you for your patience’ to many dedicated readers we can now print these two items, see Figure 1.
Gerber file

Elektor recommends its business partner Eurocircuits as the company of choice for its own prototypes and volume production in selected cases.

Component list
All parts: SMD [shape code]
Resistors:
R1,R2,R3,R12,R13 = 4k?7 [0603]
R4,R5,R10 = 47? [0805]
R6,R7,R11,R14 = 1k? [0603]
R8,R9,R17,R18,R20,R21 = 100k? [0603]
R15,R16 = 4 x 1k? [1206], resistor array
R19 = 10? [0603]
Capacitors:
C1,C4,C11,C16,C17,C18 = 470nF [0805], V? 16V
C2,C3,C6,C9,C10,C12 = 100nF [0603]
C5,C7 = 10pF [0603]
C8 = 1nF [0603]
C13 = 2µF2 [1206], V? 16V
C14,C15 = 4 x 100nF (or 47nF) [1206], capacitor array
C19,C20,C21 = 10µF 6V3
Inductor:
L1 = 100µH [1206] Rd <10?
Semiconductors:
D1 = GF1M [DO214]
D2,D3 = BZX84 [SOT23], 9V1
D4,D5 = BZX84 [SOT23], 4V7
D6 = BAW56 [SOT23]
D7 = LED, red, [0805]
T1 = BC857B
IC1 = MAX810 or similar
IC2,IC61 = 78L05 [SO8]
IC3 = MAX 487ECSA, 485, SN75176 or equivalent RS485 converter
IC4 = MSC1210 Y4 (Texas Instruments)
Miscellaneous:
K2 = 9-way sub-D plug (male), angled, PCB mount
K3 = 4-way PCB terminal block, lead pitch 5mm
K4 = 14-way pinheader (2 rows)
K5 = 34-way pinheader (2 rows)
J1,J2,J3 = jumper, 2-way, lead pitch 5mm
X1 = 11.0592MHz quartz crystal, miniature
S1 = SMD pushbutton
Order code for ready-stuffed and tested board: 030060-91.