Transfering the .s19 file to the STM8A application board

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Transfering the .s19 file to the STM8A application

board

During this phase the .s19 file is downloaded to the application board of the STM8A. If the

device is virgin, it is already in boot mode, and, the easy programmer can start to read

blocks of 128 bytes from the micro SD memory card and write them in the STM8A memory

using the boot service routine.

If the device is not virgin, and, the easy programmer has not succeeded in synchronizing

with the STM8A after three attempts, the easy programmer sends a pulse on the PH4 pin.

This pulse is captured by the STM8A application board firmware using an external I/O

interrupt. The interrupt routine (see Section 5.2: Application software on page 9) writes two

option bytes (487Eh and 487Fh) and the device is forced into boot mode. Once in boot

mode, the device starts reading and writing blocks, as described above, using the boot

service routine.

The steps are as follows:

1.

Connect the easy programmer to the STM8A application board using the connector

described in Section 5.4: Application hardware on page 10.

2.

Reset the easy programmer and wait for the LCD to display the message ‘press key to

start transfer’.

3.

Press the ‘key’ button of the easy programmer and wait until the LCD displays the

message ‘transfer OK press key’.

4.

If no errors occur, the easy programmer is ready to program another device. Otherwise,

if the LCD displays the message ‘ERROR! Boot Mode’, check the connections and

ensure the application firmware contains the interrupt routine described in Section 5.2:

Application software on page 9.