Texas Instruments Tiva TM4C123GH6PM, User Manual

Page: 19 / 352

Boot Loader
DFU_CMD_CHECK
This command is used to check a region of flash to ensure that it is completely
erased.
The start address is provided in terms of 1024-byte flash blocks. To convert a
byte address to a block address, divide by 1024. The start address must always
be on a 1024-byte boundary. The length must also be a multiple of 4.
To check that a region of flash is erased, the
DFU_CMD_CHECK
command
should be sent with the required start address and region length set then the
host should issue a
DFU_GETSTATUS
request. If the erase check was success-
ful, the returned bStatus value is OK (0x00), otherwise it is errCheckErased
(0x05).
The format of the command is as follows:
uint8_t pui8Data[8];
pui8Data[0] = DFU_CMD_CHECK (0x03)
pui8Data[1] = Reserved - set to 0x00
pui8Data[2] = Start Block Number [7:0];
pui8Data[3] = Start Block Number [15:8];
pui8Data[4] = Region Size [7:0];
pui8Data[5] = Region Size [15:8];
pui8Data[6] = Region Size [23:16];
pui8Data[7] = Region Size [31:24];
DFU_CMD_ERASE
This command is used to erase a region of flash.
The start address is provided in terms of 1024-byte flash blocks. To convert a
byte address to a block address, divide by 1024. The start address must always
be on a 1024-byte boundary. The length must also be a multiple of 4.
The size of the region to erase is expressed in terms of flash blocks. The block
size can be determined using the
DFU_CMD_INFO
command.
The format of the command is as follows:
uint8_t pui8Data[8];
pui8Data[0] = DFU_CMD_ERASE (0x04)
pui8Data[1] = Reserved - set to 0x00
pui8Data[2] = Start Block Number [7:0];
pui8Data[3] = Start Block Number [15:8];
pui8Data[4] = Number of Blocks [7:0];
pui8Data[5] = Number of Blocks [15:8];
pui8Data[6] = Reserved - set to 0x00
pui8Data[7] = Reserved - set to 0x00
April 8, 2013 19