h8s-2138 Renesas Electronics Corporation., h8s-2138 Datasheet - Page 124

• Manufacturer Part Number: h8s-2138
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Section 2 CPU
2.10
2.10.1
Only register ER0, ER1, ER4, or ER5 should be used when using the TAS instruction. The TAS
instruction is not generated by the Renesas H8S and H8/300 series C/C++ compilers. If the TAS
instruction is used as a user-defined intrinsic function, ensure that only register ER0, ER1, ER4, or
ER5 is used.
2.10.2
ER7 is not used as the register that can be saved (STM)/restored (LDM) when using STM/LDM
instruction, because ER7 is the stack pointer. Two, three, or four registers can be saved/restored by
one STM/LDM instruction. The following ranges can be specified in the register list.
Two registers: ER0–ER1, ER2–ER3, or ER4–ER5
Three registers: ER0–ER2, or ER4–ER6
Four registers: ER0–ER3
The STM/LDM instruction including ER7 is not generated by the Renesas H8S and H8/300 series
C/C++ compilers.
Rev. 4.00 Jun 06, 2006 page 70 of 1004
REJ09B0301-0400
Usage Note
TAS Instruction
STM/LDM Instruction