r4f2456 Renesas Electronics Corporation., r4f2456 Datasheet - Page 1106

• Manufacturer Part Number: r4f2456
• Description: 16-bit Single-chip Microcomputer H8s Family / H8s/2400 Series
• Manufacturer: Renesas Electronics Corporation.

Section 20 Synchronous Serial Communication Unit (SSU)
20.4.3
The connection between data input/output pins and the SS shift register (SSTRSR) depends on the
combination of the MSS and BIDE bits in SSCRH and the SSUMS bit in SSCRL. Figure 20.3
shows the relationship.
The SSU transmits serial data from the SSO pin and receives serial data from the SSI pin when
operating with BIDE = 0 and MSS = 1 (standard, master mode) (see figure 20.3 (1)). The SSU
transmits serial data from the SSI pin and receives serial data from the SSO pin when operating
with BIDE = 0 and MSS = 0 (standard, slave mode) (see figure 20.3 (2)).
The SSU transmits and receives serial data from the SSO pin regardless of master or slave mode
when operating with BIDE = 1 (bidirectional mode) (see figures 20.3 (3) and (4)).
However, even if both the TE and RE bits are set to 1, transmission and reception are not
performed simultaneously. Either the TE or RE bit must be selected.
The SSU transmits serial data from the SSO pin and receives serial data from the SSI pin when
operating with SSUMS = 1. The SSCK pin outputs the internal clock when MSS = 1 and function
as an input pin when MSS = 0 (see figures 20.3 (5) and (6)).
Rev. 1.00 Sep. 19, 2008 Page 1076 of 1342
REJ09B0467-0100
Figure 20.3 Relationship between Data Input/Output Pins and the Shift Register
(1) When SSUMS = 0, BIDE = 0 (standard mode),
(4) When SSUMS = 0, BIDE = 1 (bidirectional mode),
(5) When SSUMS = 1 and MSS = 1
MSS = 1, TE = 1, and RE = 1
MSS = 1, and either TE or RE = 1
Relationship between Data Input/Output Pins and Shift Register
Shift register
Shift register
Shift register
(SSTRSR)
(SSTRSR)
(SSTRSR)
SSCK
SSO
SSI
SSCK
SSO
SSI
SSCK
SSO
SSI
(2) When SSUMS = 0, BIDE = 0 (standard mode),
(3) When SSUMS = 0, BIDE = 1 (bidirectional mode),
(6) When SSUMS = 1 and MSS = 0
MSS = 0, TE = 1, and RE = 1
MSS = 0, and either TE or RE = 1
Shift register
Shift register
Shift register
(SSTRSR)
(SSTRSR)
(SSTRSR)
SSCK
SSO
SSI
SSCK
SSO
SSI
SSCK
SSO
SSI