Overview
This control variable is used to clear the Send buffer, Receive buffer, and error status. This control variable is write-only.
Format
If bit is specified [c:EXT_SIO_CTRL**](**:00 to 15)
If word is specified [c:EXT_SIO_CTRL]
Example expression:
When designating a bit [c:EXT_SIO_CTRL00] = 1
When designating a word [c:EXT_SIO_CTRL]= 0x0007
Contents of EXT_SIO_CTRL
When a word is selected, and two or more bits are set simultaneously, the processing is executed in the following order.
Clear error → Clear receive buffer → Clear send buffer
Clear error clears the value in status bits 1 (send error) and 3 (receive error).
For the following models, bit 0 and bit 1 is the "receive buffer clear" and "send buffer clear".
GP4000 Series
LT4000 series
SP5000 Series (excluding Open Box)
ST6000 Series
ET6000 Series
STM6000 Series
STC6000 Series
GPH6000 Series
Overview
Status includes the following information.
This status variable is write-only.
Format
If bit is specified [c:EXT_SIO_CTRL**](** :00 to 15)
If word is specified [c:EXT_SIO_CTRL]
Example expression:
When designating bit if([s:EXT_SIO_STAT00] == 1)
When designating word if(([s:EXT_SIO_STAT] & 0x0001) <> 0)
Contents of EXT_SIO_STAT
The reserved bits may be assigned in the future. Therefore, be sure to check only the necessary bits.
Two types of transmission errors exist: the transmission timeout error and the transmission buffer-full error. When either of the two errors occurs, the transmission error bit turns ON. The transmission timeout period is five seconds.
There are four types of receive errors: parity error, overrun error, framing error, and overflow. When one of these four errors occurs, the bit for the receive error turns ON.
If a transmission error is detected, the send data remains in the transmission buffer. If a transmission error cannot be detected, the send data is sent from the transmission buffer.
When using the serial interface COM2, which is RS-422, the CS (CTS) signal cannot be detected. As a result, disconnection of a cable cannot be detected.
Overview
Shows the quantity of data (number of bytes) received at that time. The received data size is read-only.
Format
[r: EXT_SIO_RCV] is the script for Receive Data Size (number of bytes) in GP-PRO/PB III V.6.0 or earlier, This script is supported and does not need to be edited. This function runs the same whether you use [r: EXT_SIO_RCV] or [r: EXT_SIO_RECV] as your expression.