<ea> indicates destination operand which field of bits have to be inserted. Offset enables to locate first bit of field; width specifies number of bits of this field. Bit field from Dn, which must be inserted in destination operand, is located in relation to bit zero. This bit zero, after insert, will have for offset: base offset more (width - 1). Be careful, this instruction operates from MSB to LSB!!
<ea> ----------------------------------------========================= |15 |14 |13 |12 |11 |10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |---|---|---|---|---|---|---|---|---|---|-----------|-----------| | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | MODE | REGISTER | |---|-----------|---|-------------------|-----------------------| | 0 | REGISTER |Do | OFFSET |Dw | WIDTH | ----------------------------------------------------------------- If Do = 0->Field "OFFSET" contains an immediate value which represents effective offset, value from 0 to 31. If Do = 1->Field "OFFSET" indicates number of a data register (bits 9 and 10 of field cleared) which contains effective offset. Signed value is represented on 32 bits., so it's extended from -2 EXP 31 to (+2 EXP 31) -1. If Dw = 0->field "WIDTH" contains an immediate value between 1 and 31 which indicates a width from 1 to 31 bits. A value of 0 indicates a width of 32 bits. If Dw = 1->field "WIDTH" indicates number of a data register (bits 3 and 4 of field cleared) which contains width of bit field. The value modulo 32 can go from 1 to 31, indicating a width from 1 to 31 bits. A value 0 indicates a width of 32 bits. REGISTER <ea> specifies destination, addressing modes are the followings: --------------------------------- ------------------------------- |Addressing Mode|Mode| Register | |Addressing Mode|Mode|Register| |-------------------------------| |-----------------------------| | Dn |000 |No reg. Dn| | (Abs).W |111 | 000 | |-------------------------------| |-----------------------------| | An | - | - | | (Abs).L |111 | 001 | |-------------------------------| |-----------------------------| | (An) |010 |No reg. An| | (d16,PC) | - | - | |-------------------------------| |-----------------------------| | (An)+ | - | - | | (d8,PC,Xi) | - | - | |-------------------------------| |-----------------------------| | -(An) | - | - | | (bd,PC,Xi) | - | - | |-------------------------------| |-----------------------------| | (d16,An) |101 |No reg. An| |([bd,PC,Xi],od)| - | - | |-------------------------------| |-----------------------------| | (d8,An,Xi) |110 |No reg. An| |([bd,PC],Xi,od)| - | - | |-------------------------------| |-----------------------------| | (bd,An,Xi) |110 |No reg. An| | #data | - | - | |-------------------------------| ------------------------------- |([bd,An,Xi],od)|110 |No reg. An| |-------------------------------| |([bd,An],Xi,od)|110 |No reg. An| ---------------------------------
X - not affected N - Set if MSB of field is set. Cleared otherwise. Z - Set if all the bits of the field tested are zero. Cleared otherwise. V - Always cleared. C - Always cleared.