SPRU513Z August 2001 – October 2023 SM320F28335-EP
The Motorola S1, S2, and S3 formats support 16-bit, 24-bit, and 32-bit addresses, respectively. The formats consist of a start-of-file (header) record, data records, and an end-of-file (termination) record. Each record consists of five fields: record type, byte count, address, data, and checksum. The three record types are:
Record Type | Description |
---|---|
S0 | Header record |
S1 | Code/data record for 16-bit addresses (S1 format) |
S2 | Code/data record for 24-bit addresses (S2 format) |
S3 | Code/data record for 32-bit addresses (S3 format) |
S7 | Termination record for 32-bit addresses (S3 format) |
S8 | Termination record for 24-bit addresses (S2 format) |
S9 | Termination record for 16-bit addresses (S1 format) |
The byte count is the character pair count in the record, excluding the type and byte count itself.
The checksum is the least significant byte of the 1s complement of the sum of the values represented by the pairs of characters making up the byte count, address, and the code/data fields.
Figure 12-11 illustrates the Motorola-S object format.