Datasheet

Section 7 ROM
Page 196 of 982 REJ09B0465-0300 Rev. 3.00
Sep 17, 2010
H8S/20103, H8S/20203, H8S/20223, H8S/20115, H8S/20215, H8S/20235 Group
(9) Command Errors
Command errors are caused by undefined commands, incorrect command sequence, and
unacceptable commands. For example, sending a clock-mode selection command before a device
selection command and sending an inquiry command after a programming/erasure state transition
command both cause command errors.
Error response
H'80 H'xx
• Error response H'80 (1 byte): Command error
• Command H'xx (1 byte): Received command
(10) Order of Commands
In the inquiry/selection state, commands should be sent in the following order.
1. Send the supported-device inquiry command (H'20) to get the list of supported devices.
2. Select a device according to the returned device information, and send the device selection
command (H'10).
3. Send the clock-mode inquiry command (H'21) to inquire about clock modes.
4. Select a clock mode from among the returned clock modes, and send the clock-mode selection
command (H'11).
5. After selection of the device and clock mode, send the frequency-division-ratio inquiry
command (H'22) and operating-frequency inquiry command (H'23) to get the information
necessary for selecting a new bit rate.
6. Select a new bit rate according to the returned information on the frequency division ratios and
operating frequencies, send the new bit-rate selection command (H'3F).
7. After selection of the new bit rate, send the programmable ROM information inquiry
command (H'25), erasure-block-information inquiry command (H'26), and programming-size
inquiry command (H'27) to get the information necessary for programming/erasing the user
ROM area.
8. After each inquiry of step [7], send the programming/erasure state transition command (H'40)
to cause a transition to the programming/erasure state.