Data Sheet

dS1242

dS1242 User Manual v4.03

Function 05 (0x05) Write Single Coil

This function is used to write to a single coil (relay or I/O). Coils 1-2 are the relays 1-2. Coils

41-44 are the I/O's 1-4 remapped to coils 41-44.

Function 15 (0x0F) Write Multiple Coils

Use this function when you need to write to multiple relays and I/O’s at the same time.

Coils 1-2 are the relays 1-2. Coils 41-44 are the I/O's 1-4 remapped to coils 41-44.

Error code 1

This error is returned if an unknown or unimplemented function is received. Only functions 1,

4, 5 & 15 are implemented.

Error code 2

This error is returned if an illegal address is requested. Addresses greater than 15 for functions

1 & 5 or greater than 7 for function 4 will generate this error.

Error code 3

This error is returned if an illegal data value is received. Number of points = zero will generate

this as will an illegal data value for function 5.