SH7059 Datasheet, PDF (795/1042 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer

24. ROM (SH7058S)
Command H'3F
Size
Bit rate
Input frequency
Number of
Multiplication Multiplication
multiplication ratios ratio 1
ratio 2
SUM
⎯ Command: H'3F (one byte): Selection of new bit rate
⎯ Size (one byte): Amount of data that represents the bit rate, input frequency, number of multiplication ratios, and
multiplication ratios
⎯ Bit rate (two bytes): New bit rate
One hundredth of the value (e.g. when the value is 19200 bps, the bit rate is 192, which is H'00C0)
⎯ Input frequency (two bytes): Frequency of the clock input to the boot program
This value is valid to the hundredths place and represents the value in MHz multiplied by 100. (e.g. when the value
is 28.88 MHz, it will be multiplied by 100 to be 2888 which is H'0B48.
⎯ Number of multiplication ratios (one byte): Number of multiplication ratios to which the device can be set.
⎯ Multiplication ratio 1 (one byte): Value of the multiplication or division ratio for the main operating frequency
Multiplication ratio: Value of the multiplication ratio (e.g. when the clock frequency is multiplied by four, the
multiplication ratio will be H'04.)
Division ratio: Value of the division ratio, inverted to be a negative number (e.g. when the clock is divided by two,
the value of division ratio will be H'FE. H'FE = −2)
⎯ Multiplication ratio 2 (one byte): Value of the multiplication or division ratio for the peripheral operating frequency
Multiplication ratio: Value of the multiplication ratio (e.g. when the clock frequency is multiplied by four, the
multiplication ratio will be H'04.)
Division ratio: Value of the division ratio, inverted to be a negative number (e.g. when the clock is divided by two,
the value of division ratio will be H'FE. H'FE = −2)
⎯ SUM (one byte): Checksum
Response H'06
⎯ Response: H'06 (one byte): Response to selection of a new bit rate
When it is possible to set the bit rate, the response will be ACK.
Error response H'BF ERROR
⎯ Error response: H'BF (one byte): Error response to selection of new bit rate
⎯ ERROR: (one byte): Error code
H'11: Checksum error
H'24: Bit-rate selection error
This bit rate is not available.
H'25: Input frequency error
This input frequency is not within the range set by the minimum and maximum
values.
H'26: Multiplication ratio error
This ratio does not match an available ratio.
H'27: Operating frequency error
This operating frequency is not within the range set by the minimum and
maximum values.
The methods for checking of received data are listed below.
• Input frequency
The received value of the input frequency is checked to ensure that it is within the range of minimum to
maximum frequencies which matches the clock modes of the specified device. When the value is out of this
range, an input frequency error is generated.
• Multiplication ratio
The received value of the multiplication ratio or division ratio is checked to ensure that it matches the clock
modes of the specified device. When the value is out of this range, a multiplication error is generated.
Rev.3.00 Mar. 12, 2008 Page 705 of 948
REJ09B0177-0300