POWERSTEP01 datasheet(74/92 Pages) STMICROELECTRONICS

74 / 92 page

Programming manual

powerSTEP01

74/92

DocID025022 Rev 5

11.2.1

Command management

The host microcontroller can control motor motion and configure the powerSTEP01 through

a complete set of commands.

All commands are composed by a single byte. After the command byte, some bytes of

arguments should be needed (see Figure 27). Argument length can vary from 1 to 3 bytes.

Figure 27. Command with 3-byte argument

By default, the device returns an all zero response for any received byte, the only

exceptions are GetParam and GetStatus commands. When one of these commands is

received, the following response bytes represent the related register value (see Figure 28).

Response length can vary from 1 to 3 bytes.

Figure 28. Command with 3-byte response

During response transmission, new commands can be sent. If a command requiring

a response is sent before the previous response is completed, the response transmission is

aborted and the new response is loaded into the output communication buffer (see

Figure 29).

Figure 29. Command response aborted

When a byte that does not correspond to a command is sent to the IC it is ignored and the

CMD_ERROR flag in the STATUS register is raised (see paragraph Section 11.1.28).

POWERSTEP01 Datasheet(PDF) 74 Page - STMicroelectronics