Campbell Scientific CR10 CR10 Measurement and Control - Page 133

Pulse duration, initiated by a program control instruction, can be set for each control port (Table 12-2). lnstruction 20 does not pulse the port, it only sets the duration. lf Instruction 20 is not used to set the duration, the pulse command will result in a 10 ms pulse. Instruction 20 has two 4 digit parameters. Each digit represents one control port. The code (09) entered as the digit determines what effect command 20 has on the corresponding port. TABLE 9-5. Port Configuration Option Codes Code Function 0 Set port low 1 Set port high 2 Toggle port 3 Pulse duration 1 ms 4 Pulse duration 10 ms 5 Pulse duration 100 ms 6 Pulse duration 1 s 7 Configure as output I Configure as input 9 Leave unchanged Duration of pulse on subsequent pulse port command in Program Control lnstruction. PARAM. DATA NUMBER ryPE DESCR]PTION :01 4 O2'. 4 C8, C7, C6, C5 oPtion codes C4, C3, C2, C1 oPtion codes Input locations altered: 0 *** 22 EXCITATION WITH DELAY *** FUNCTION This instruction is used in conjunction with others for measuring a response to a timed excitation using the switched analog outputs. lt sets the selected excitation output to a specific value, waits for the specified time, then turns off the excitation and waits an additionalspecified time before continuing execution of the following instruction. Analog power is turned off during delay after excitation to drop power to 3 mA. lf the only requirement is the delay of program execution, the excitation on time (parameter 2) can be set to zero and the off time delay (parameter 3) can be used. SECTION 9. INPUT/OUTPUT INSTRUCTIONS PARAM. DATA NUMBER TYPE DESCRIPTION 01: 2 Excitation channel 02: number 4 Delay time in hundredths of a second 03: 04: 4 FP that excitation is on Delay time in hundredths of a second after excitation is turned off Excitation voltage in millivolts Input locations altered: 0 *** 23 BURST MEASUREMENT *** FUNCTION lnstruction 23 will repeatedly make a voltage measurement on a series of single-ended or differential channels, applying excitation if desired. The measurement units are millivolts prior to scaling. The measurements saved can be those made immediately upon execution of the instruction or grouped around a specified trigger condition. The results of the measurements may be stored in lnput Storage or the raw A/D data can be sent out the serial port. The minimum sample time per channel is 1.333 ms (i.e., one channel can be sampled at a maximum rate of 750 Hz). MEASUREMENT The voltage measurement must use the fast integration time of 2721ts. Differential measurements are made with a single integration. The noise level on a fast singleended or a differential measurement with 1 integration is 3 pV RMS. Thus, only the 25 mV and greater voltage ranges are practical (range codes 13-15). Excitation is always supplied f rom .excitation channel 1. The excitation voltage in millivolts is entered in Parameter 9. lf excitation is not desired, enter 0 for Parameter 9. Three options are available for the first digit in Parameter 4. 0 - Trigger on first measurement channel. 1 - Trigger on Digital Control Port 1. 2 - Trigger on first measurement channel, set Digital Control Port high when trigger is met and low when measurements have finished. When triggering on options 0 or 2, the measurement on the first specified channel (Parameter 3) is compared to the limit specified 9-9