Current ESP-01 firmware versions do not have an AT+IPR command. If you're trying to change the ESP's baud rate to use it with SoftwareSerial, the command to do so (in recent versions of the firmware) is: AT+9600,8,1,0,0 for 9600 baud, 1 stop bit, no parity, no flow control.

The full syntax is:
AT+UART=<baudrate>, <databits>, <stopbits>, <parity>, <flow control>
, where <databits> is the number of data bits per frame, 5,6,7,or 8; <stopbits> is 1, 2, or 3 for 1, 1.5, or 2 stopbits (respectively); <parity> is 0, 1, or 2 for None, Odd, Even (respectively); and <flow control> is 0, 1, 2, or 3 for None, RTS, CTS, RTS and CTS (respectively). Most serial communication and devices that most of us will ever see will be 8 data bits, no parity, and 1 stop bit, abbreviated as "8N1". Flow control is sometimes used, but often it is contained in the data stream itself, such as sending Ctl-S and Ctl-Q from the keyboard to manually stop and resume incoming data transmission.

Current ESP-01 firmware versions do not have an AT+IPR command. If you're trying to change the ESP's baud rate to use it with SoftwareSerial, the command to do so (in recent versions of the firmware) is: AT+UART=9600,8,1,0,0 for 9600 baud, 1 stop bit, no parity, no flow control.

The full syntax is:
AT+UART=<baudrate>, <databits>, <stopbits>, <parity>, <flow control>
, where <databits> is the number of data bits per frame, 5,6,7,or 8; <stopbits> is 1, 2, or 3 for 1, 1.5, or 2 stopbits (respectively); <parity> is 0, 1, or 2 for None, Odd, Even (respectively); and <flow control> is 0, 1, 2, or 3 for None, RTS, CTS, RTS and CTS (respectively). Most serial communication and devices that most of us will ever see will be 8 data bits, no parity, and 1 stop bit, abbreviated as "8N1". Flow control is sometimes used, but often it is contained in the data stream itself, such as sending Ctl-S and Ctl-Q from the keyboard to manually stop and resume incoming data transmission.

Current ESP-01 firmware versions do not have an AT+IPR command. If you're trying to change the ESP's baud rate to use it with SoftwareSerial, the command to do so (in recent versions of the firmware) is: AT+9600,8,1,0,0 for 9600 baud, 1 stop bit, no parity, no flow control.

The full syntax is: AT+UART=<baudrate>, <databits>, <stopbits>, <parity>, <flow control>, where <databits> is 5,6,7,8; <stopbits> is 1, 2, or 3 for 1, 1.5, or 2 stopbits (respectively); <parity> is 0, 1, or 2 for None, Odd, Even (respectively); and <flow control> is 0, 1, 2, or 3 for None, RTS, CTS, RTS and CTS (respectively).

Current ESP-01 firmware versions do not have an AT+IPR command. If you're trying to change the ESP's baud rate to use it with SoftwareSerial, the command to do so (in recent versions of the firmware) is: AT+9600,8,1,0,0 for 9600 baud, 1 stop bit, no parity, no flow control.

The full syntax is: 
AT+UART=<baudrate>, <databits>, <stopbits>, <parity>, <flow control> 
, where <databits> is the number of data bits per frame, 5,6,7,or 8; <stopbits> is 1, 2, or 3 for 1, 1.5, or 2 stopbits (respectively); <parity> is 0, 1, or 2 for None, Odd, Even (respectively); and <flow control> is 0, 1, 2, or 3 for None, RTS, CTS, RTS and CTS (respectively). Most serial communication and devices that most of us will ever see will be 8 data bits, no parity, and 1 stop bit, abbreviated as "8N1". Flow control is sometimes used, but often it is contained in the data stream itself, such as sending Ctl-S and Ctl-Q from the keyboard to manually stop and resume incoming data transmission.