Sun Microsystems S16A manual Uart Command/Status Register, Write to a Trim Register

Registers S16A User’s Guide

Write to a Trim Register

The trim registers are written by sending a four-byte sequence beginning with D or w.

Dnmm	Write an 8-bit value to a trim register.
	n	Number of the trim register to be written:
		2	Output 0 offset
		3	Output 1 offset
		4	Input 0 gain trim
		5	Input 0 offset
		6	Input 1 gain trim
		7	Input 1 offset
	mm	Hexadecimal value to write to the register.

The UART responds with the four-character sequence return linefeed > space.

Read the Temperature Register

The Temperature register is read by sending a one-byte command: T or t.

T Read the Temperature register.

The UART responds with the seven-character sequence xxx return linefeed > space, where xxx is the three- character hexadecimal value. See Temperature Register beginning on page 34 for details on how to interpret this value.

UART Command/Status Register

The UART CSR is an 8-bit register at 0400C0x. This register controls the serial byte-stream protocol used to configure and control the internal analog input module.

Bit	S16A_	Description
7	UART_INT	A read-only status bit. A value of 1 indicates the S16A UART is asserting
		an SBus interrupt.
6		Unused. 0 when read.
5	UART_TXBSY	A read-only status bit. A value of 1 indicates the S16A UART is currently
		transmitting a command byte to the analog input module. No other bytes
		can be sent until this bit is clear.
4	UART_RXRDY	A read-only status bit. A value of 1 indicates the S16A UART has received
		a status byte from the analog input module. Valid status bytes can only be
		read from the UART_DATA register when this bit is set.
3	UART_TXINT	A value of 1 enables the UART transmit complete interrupt.
2	UART_TXINT	A value of 1 enables the UART receive complete interrupt.
1–0		Unused. 0 when read.

Table 16. UART Command/Status Register

36 EDT, Inc. October, 1996