Knowledge Base

This section describes the specifics of the SPice connectors on the MS120. The SPice expansion scheme in general is documented elsewhere in the SPLat Knowledge Base, under the SPLat Expansion Framework.

The MS120 has 2 SPice connectors. These are labeled SPice (the “main” one) and SPiceII (Roman numeral 2). The former is virtually identical electrically and mechanically to the single SPice connectors on MMi99, MMi200 and SL99 controllers. The latter is unique to the MS120. Note the MS120 does not support TSP.

The main SPice connector supports the same SPice boards that work on MMi and SL family products.

The SPiceII is different. It allows us to make SPice boards that are uniquely for the MS120 and straddle both connectors. You can still only use one SPice board.

The SPice connector signals are as follows:

CnctrPin#As inputAs outputAs AnInAs AnOutU(n)Comments
SPice1Raw positive board supply voltage
SPice2+5V regulated. Permissible load 15mA
SPice3Not used (Other products have a -ve bias generator in this pin, but not the MS120)
SPice41712*C (2) 0 
SPice51813*D (3) 1 
SPice61914*E (4) 2 
SPice72015*F (5) 3 
SPice82116* J (9)4 
SPice92217 I (8)*5 
SPice10,11,120V (system ground)
 
SPice-II1Raw positive board supply voltage
SPice-II2+5V regulated. Permissible load 15mA
SPice-II32318*G (6) 6 
SPice-II42419*H (7) 7 
SPice-II52520*  8Also LCD B/light
SPice-II62621* K (10)9 
SPice-II72722* L (11)10 
SPice-II8     Comms Rx (in)
SPice-II9     Comms Tx (out)
SPice-II100V (system ground)

* Default settings are marked *

The U(n) column refers to the position in U of the pin’s configuration byte during a SPiceConfigU instruction.

Analog channel designators are show both in the old letter style and the newer (dialect 18 floating point analog I/O) numeric channel numbers.

The I/O pins can be set up for different functions for use with different SPice boards. The function of the pins is set in your program using the SPiceConfigU instruction.

One pin is shared with the LCD backlight control. If an LCD is fitted that pin is not available for any other use.

Note that the LCD backlight, output 20, defaults to OFF. Your program must turn it on if you are using the optional onboard LCD. See also Example LCD backlight auto-off timers.

The analog output function is actually a pulse width modulated (PWM) digital output. On a SPice board this can be filtered to yield a smooth DC voltage, giving an analog output.

The 15mA permissible load on the +5V supply pin is a nominal allowance, aggregate for the two connectors, that has been included in the overall power supply budget with board supply voltages up to the maximum rating of 32V. This can be increased significantly if lower supply voltages are used.

The raw board supply voltage referred to is as selected by the power jumper.

Comms Rx and Tx are the same signals that appear on the comms connector. They are CMOS/TTL voltage levels, not RS232. Being available on the SPice-II means we can make SPice boards with communications capabilities.

We do not intend users to use the SPice connector other than for add-on boards supplied by us. The above information is provided mainly to make you aware of the possibilities, perhaps to inspire you to have a custom SPice board made.