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Send the service init command one byte at a time

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The hwOS firmware reads the service init command one byte at a time, and
sends the echo immediately after each byte.

Reported-by: Ralph Lembcke <mail@ralph-lembcke.de>
This commit is contained in:
Jef Driesen 2020-03-10 21:48:36 +01:00
parent 94cd864dba
commit d1b865d192
1 changed files with 32 additions and 21 deletions
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53
src/hw_ostc3.c
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@ -69,6 +69,7 @@
#define S_UPLOAD 0x73
#define WRITE 0x77
#define RESET 0x78
#define S_INIT 0xAA
#define INIT 0xBB
#define EXIT 0xFF
@ -456,33 +457,43 @@ hw_ostc3_device_init_service (hw_ostc3_device_t *device)
{
dc_status_t status = DC_STATUS_SUCCESS;
dc_device_t *abstract = (dc_device_t *) device;
dc_context_t *context = (abstract ? abstract->context : NULL);
unsigned char command[] = {0xAA, 0xAB, 0xCD, 0xEF};
unsigned char output[5];
const unsigned char command[] = {S_INIT, 0xAB, 0xCD, 0xEF};
unsigned char answer[5] = {0};
// We cant use hw_ostc3_transfer here, due to the different echos
status = hw_ostc3_write (device, NULL, command, sizeof (command));
for (size_t i = 0; i < 4; ++i) {
// Send the command.
status = hw_ostc3_write (device, NULL, command + i, 1);
if (status != DC_STATUS_SUCCESS) {
ERROR (abstract->context, "Failed to send the command.");
return status;
}
// Read the answer.
status = hw_ostc3_read (device, NULL, answer + i, 1);
if (status != DC_STATUS_SUCCESS) {
ERROR (abstract->context, "Failed to receive the answer.");
return status;
}
// Verify the answer.
const unsigned char expected = (i == 0 ? 0x4B : command[i]);
if (answer[i] != expected) {
ERROR (abstract->context, "Unexpected answer byte.");
return DC_STATUS_PROTOCOL;
}
}
// Read the ready byte.
status = hw_ostc3_read (device, NULL, answer + 4, 1);
if (status != DC_STATUS_SUCCESS) {
ERROR (context, "Failed to send the command.");
ERROR (abstract->context, "Failed to receive the ready byte.");
return status;
}
// Give the device some time to enter service mode
dc_iostream_sleep (device->iostream, 100);
// Read the response
status = hw_ostc3_read (device, NULL, output, sizeof (output));
if (status != DC_STATUS_SUCCESS) {
ERROR (context, "Failed to receive the echo.");
return status;
}
// Verify the response to service mode
if (output[0] != 0x4B || output[1] != 0xAB ||
output[2] != 0xCD || output[3] != 0xEF ||
output[4] != S_READY) {
ERROR (context, "Failed to verify echo.");
// Verify the ready byte.
if (answer[4] != S_READY) {
ERROR (abstract->context, "Unexpected ready byte.");
return DC_STATUS_PROTOCOL;
}